diff --git a/docs/context/adrs/ADR-0001-marketplace-platform-vision.md b/docs/context/adrs/ADR-0001-marketplace-platform-vision.md
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+---
+id: ADR-0001
+title: Multi-tenant marketplace platform vision and config-driven architecture
+status: active
+date: 2026-07-13
+tags: ["architecture", "philosophy", "multi-tenant", "bootstrap"]
+---
+
+## Context
+
+This is not a single marketplace — it is a multi-tenant platform powering unlimited
+marketplaces (e.g. electronics.example.com, books.example.com) from one codebase.
+Every marketplace is configured from the backend via a bootstrap configuration
+(`GET /bootstrap`). No marketplace-specific code may exist in the frontend.
+
+## Decision
+
+- The frontend (Angular 20, standalone components, Signals, RxJS, SCSS) is a pure
+  renderer. It owns render, navigation, interaction, validation, animations only.
+- The backend (ASP.NET Core REST API) owns branding, pages, layouts, languages,
+  homepage, navigation, categories, products, footer, static pages, payment
+  configuration, and enabled features.
+- Flow: Bootstrap → Runtime Provider → Configuration Store → Renderer → Widgets.
+  Nothing depends on build-time environments; everything depends on runtime
+  configuration.
+- Bootstrap contains only data needed before the app starts (name, logo, colors,
+  languages, footer pages, homepage layout, navigation, enabled widgets). It must
+  never contain products, orders, cart, or users.
+- Widgets never own page spacing — only their own internal layout. The renderer
+  owns sections, spacing, and page width.
+- Homepage is composed from a configurable, ordered list of sections (Section
+  Engine): Hero, Categories, Featured Products, Banner, Latest Products, Custom
+  HTML, Newsletter, etc.
+- All layouts (homepage, PLP, etc.) must be backend-configurable without frontend
+  changes.
+- All user-facing text is translatable via a `translations.{lang}` shape, not a
+  flat `title` field. Adding/removing a supported language must automatically
+  expose/remove translation fields across all translatable objects, generically —
+  never per-field hardcoding.
+- Static pages (About Us, Privacy, Terms, Contacts, Return Policy, Delivery,
+  custom pages) are backend-delivered HTML, multilingual, and drive the footer.
+- Admin and storefront share a domain but are fully separate applications: the
+  marketplace bundle never ships admin code and vice versa. Bootstrap is public;
+  Admin is protected by JWT + roles/permissions + tenant isolation (Super Admin,
+  Marketplace Admin, Moderator, Editor, Support, Customer).
+
+## Coding rules
+
+- Never hardcode marketplace data or introduce marketplace-specific conditionals.
+- Never use environment flags to drive UI — everything is config-driven.
+- Keep components small; prefer composition and reusable widgets; never
+  duplicate layouts.
+- Business logic lives in services/facades, not components.
+- Prefer Signals and standalone components.
+- Every new feature ships with docs: frontend docs, backend contract, bootstrap
+  updates, API examples, migration notes if needed.
+
+## Guiding question
+
+Before implementing anything: "Will this still make sense after 50 marketplaces
+and 100 developers?" If not, redesign before coding.
+
+## Consequences
+
+Any feature (including the Sprint 16 Project Editor) must edit the same Bootstrap
+model the storefront consumes — no parallel/duplicate configuration models are
+permitted anywhere in the platform.
diff --git a/docs/context/features/platform-vision/FACTS.jsonl b/docs/context/features/platform-vision/FACTS.jsonl
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+{"id":"PV-20260713T000000Z-0001","subject":"platform","predicate":"is-architected-as","object":"multi-tenant marketplace platform powering unlimited marketplaces from one codebase, driven entirely by backend bootstrap configuration","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"decision","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["architecture","multi-tenant"]}
+{"id":"PV-20260713T000000Z-0002","subject":"frontend","predicate":"must-not","object":"contain marketplace-specific code, hardcoded marketplace data, or environment-flag-driven UI","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"constraint","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["frontend","constraint"]}
+{"id":"PV-20260713T000000Z-0003","subject":"bootstrap","predicate":"must-only-contain","object":"data needed before app start (branding, languages, homepage layout, navigation, enabled widgets, footer pages) and must never contain products, orders, cart, or users","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"constraint","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["bootstrap","constraint"]}
+{"id":"PV-20260713T000000Z-0004","subject":"translatable-fields","predicate":"must-be-modeled-as","object":"generic translations.{lang} map so adding/removing a language automatically exposes/removes translation fields across all translatable objects","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"constraint","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["i18n","constraint"]}
+{"id":"PV-20260713T000000Z-0005","subject":"admin-app","predicate":"is-isolated-from","object":"marketplace storefront bundle: admin code never ships to storefront and vice versa, though they may share a domain","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"constraint","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["admin","security"]}
+{"id":"PV-20260713T000000Z-0006","subject":"widgets","predicate":"must-not-own","object":"page spacing or page width; the renderer owns sections, spacing, and page width, widgets own only their internal layout","src":["docs/context/adrs/ADR-0001-marketplace-platform-vision.md"],"status":"active","kind":"constraint","updated_at":"2026-07-13T00:00:00Z","confidence":"high","tags":["widgets","layout"]}
diff --git a/docs/superpowers/specs/2026-07-13-marketplace-project-editor-sprint16-design.md b/docs/superpowers/specs/2026-07-13-marketplace-project-editor-sprint16-design.md
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+++ b/docs/superpowers/specs/2026-07-13-marketplace-project-editor-sprint16-design.md
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+# Sprint 16 — Marketplace Project Editor MVP
+
+Status: approved for planning
+Date: 2026-07-13
+Related: [ADR-0001](../../context/adrs/ADR-0001-marketplace-platform-vision.md), [Project-Editor.md](../../Project-Editor.md)
+
+## Goal
+
+A client can open the editor for their marketplace, edit settings, save a
+draft, preview, and publish — without touching JSON by hand. The editor edits
+the same `BootstrapConfig` the storefront consumes. No parallel/duplicate
+configuration model is introduced anywhere in this work.
+
+## Current state (as of this sprint)
+
+A working editor already exists at `/builder`
+(`src/app/features/project-editor/`): `ProjectEditorPageComponent` + signal-based
+`ProjectEditorFacade` (no NgRx), sections for general, branding, theme, header,
+footer, homepage (already has drag-and-drop reordering), widgets,
+static-pages (via `StaticPagesEditorComponent`), features, preview. Static
+page HTML is edited via a plain `<textarea>`. There is no Languages tab, no
+Navigation tab, no Draft/Publish distinction, and no `ProjectValidator`. There
+is no separate admin app — admin-ish features are ordinary lazy routes in the
+same Angular build as the storefront. There is no `projectId` / multi-project
+concept: each domain (tenant) resolves to its own bootstrap via the existing
+tenant-resolution mechanism, so "a project" is implicitly the current domain's
+tenant.
+
+This sprint extends the existing editor rather than rebuilding it.
+
+## Routing
+
+Single Angular build (no separate admin app this sprint — deferred, see
+Out of scope). Flat, non-parameterized routes, since there is no project id:
+
+```
+/edit                  → redirect to /edit/general
+/edit/general
+/edit/branding
+/edit/theme            (existing, kept)
+/edit/languages        (new)
+/edit/navigation       (new)
+/edit/header           (existing, kept)
+/edit/homepage
+/edit/footer
+/edit/static-pages
+/edit/widgets          (existing, kept)
+/edit/features         (existing, kept)
+/edit/preview
+```
+
+`/builder` and `/builder/*` redirect to the equivalent `/edit/*` route for
+backward compatibility. Actual subdomain hosting (`admin.marketplace.com`)
+and a physically separate Angular deployment are a future ADR/sprint — this
+sprint only makes the route shape subdomain-ready (flat, no id segment).
+
+Tabs become real child routes (deep-linkable, back-button works) instead of
+today's in-component signal switch. `ProjectEditorFacade` is unchanged by
+this — it already loads/holds bootstrap independent of which tab is active.
+
+## Languages tab (new)
+
+New `LocaleSyncService` (in `features/project-editor/services/`). It knows
+both translation shapes already used in the codebase:
+- index-signature maps: `{ [locale: string]: string }`
+  (`LocalizedTextContent`/`LocalizedHtmlContent`)
+- keyed translation records: `Record<string, { title?, html?, seo? }>`
+  (e.g. `StaticPageTranslationConfig`)
+
+`addLocale(code)` / `removeLocale(code)` walk the known translatable slices of
+the in-memory bootstrap draft (static pages, footer nav labels, homepage
+widget text props) and add/remove that locale's key generically — not one
+`if` per field. `setDefaultLocale(code)` updates
+`localization.defaultLocale` (already exists). The tab lists supported
+locales, lets you add/remove, and pick the default; removing the current
+default is blocked by `ProjectValidator` (see below).
+
+## Navigation tab (new)
+
+Visual nested list over header + footer navigation
+(`src/app/shared/models/config/navigation.model.ts`). Add link, remove link,
+reorder (buttons, matching the homepage tab's existing pattern — no new
+drag-and-drop library), edit label (multilingual, via the same translation
+shape as everywhere else), edit URL, "open in new tab" toggle, visibility
+toggle, and nested children. Backed by new facade actions on
+`ProjectEditorFacade` (`addNavLink`, `removeNavLink`, `reorderNavLink`,
+`updateNavLink`) — no new store, same facade.
+
+## Rich HTML editor (new)
+
+New `MarketplaceHtmlEditorComponent`
+(`features/project-editor/components/html-editor/`): native
+`contentEditable` + a toolbar (bold, italic, underline, bullet/numbered
+lists, link, image, table, headings, code view, preview). No new npm
+dependency (no Quill/TipTap). Emits raw HTML on change; does not sanitize —
+sanitization remains a storefront-render concern, unchanged. Replaces the
+`<textarea>` currently in `static-pages-editor.component.html`, and is reused
+anywhere else HTML is edited going forward (e.g. footer custom content).
+
+## Draft / Publish
+
+No backend draft/publish API exists yet — confirmed against
+`docs/Project-Editor.md`, which only lists *recommended future* endpoints
+(`PUT /builder/bootstrap`, `POST /builder/bootstrap/{preview,validate,import}`,
+`GET /builder/bootstrap/export`), none of which distinguish draft from
+published. This sprint models it client-side only:
+
+- `ProjectDraft` (new, in `models/`): `{ bootstrap: BootstrapConfig, status:
+  'draft' | 'published', dirty: boolean, lastSavedAt?: string }`.
+- **Save** persists the draft using the same local mechanism the editor
+  already uses for export/import (no new backend call this sprint) and
+  clears `dirty`.
+- **Publish** runs `ProjectValidator` (must pass), then calls
+  `ConfigService.applyBootstrapOverride()` (the mechanism already used for
+  live preview) and sets `status = 'published'`.
+- **Documented gap for backend**: real draft/publish persistence needs
+  `PUT /builder/bootstrap/draft` and `POST /builder/bootstrap/publish`
+  endpoints. Not implemented this sprint; called out explicitly so backend
+  work can be scheduled.
+
+## Validation (new)
+
+New `ProjectValidator` (in `services/`), pure functions run against the
+current draft. Checks: missing logo, no languages configured, invalid
+marketplace URL, duplicate static-page slugs, empty homepage (no sections),
+homepage section referencing a missing/unregistered widget, duplicate
+navigation links (same URL+label pair), invalid color values (theme tab).
+Runs on every Save (surfaces warnings, does not block) and on Publish
+(blocks with a clear list of failures). Errors surface inline in the
+relevant tab plus a summary list.
+
+## Dirty-state
+
+`ProjectEditorFacade` tracks `dirty` via a diff against the last-saved
+snapshot. A `CanDeactivate` route guard plus a `beforeunload` listener warn
+before navigating away or closing the tab with unsaved changes.
+
+## UI
+
+Card-based layout per tab, sticky Save/Publish bar (shows dirty state and
+validation summary), responsive down to tablet width — matching the
+existing editor's current visual style, no new design system.
+
+## Architecture summary
+
+Reused as-is: `ProjectEditorFacade`, `ProjectEditorIoService`,
+`ProjectEditorPreviewService`, existing section components.
+
+New: `LocaleSyncService`, `ProjectValidator`, `MarketplaceHtmlEditorComponent`,
+`ProjectDraft` model, Navigation tab section + facade actions, Languages tab
+section + facade actions, `CanDeactivate` dirty-guard.
+
+No `ProjectEditorStore`/`ProjectSerializer` as separate classes — the
+existing facade + `ProjectEditorIoService` already cover that responsibility
+(store = facade signals; serializer = IO service); introducing parallel
+classes would duplicate what's there, which the platform's own coding rules
+forbid.
+
+## Out of scope (this sprint)
+
+- Separate Angular app / actual subdomain deployment for admin.
+- Real backend draft/publish persistence (documented as a gap above).
+- Drag-and-drop for the new Navigation tab (buttons only, like homepage's
+  existing pattern predates this — homepage itself already has drag-and-drop
+  from a prior sprint and is left as-is).
+- Products, Orders, Users, Dashboards, Analytics (future sprints per the
+  platform roadmap).
+
+## Documentation
+
+This spec plus updates to `docs/Project-Editor.md` (new tabs, draft/publish
+model, new services) and a fact-pack update under
+`docs/context/features/project-editor/FACTS.jsonl` are part of the
+deliverable, per the platform's documentation rule ("every new feature must
+include documentation").