fix(editor): remove dangling Header 'Profile' toggle

P0-7: the Project Editor's header-section exposed a 'Profile'
toggle (HeaderConfig.showProfile) with no corresponding UI anywhere
in the storefront header — confirmed dead per docs/KNOWN-ISSUES.md
item 5. Toggling it implied a feature (an account/profile menu)
that doesn't exist, which is misleading in the editor.

Building the actual account/profile surface is real feature work
(out of scope for this polish pass), so removed the toggle from the
editor's items list and the field-schema registry instead of
building UI a merchant would flip with no visible effect. The
underlying HeaderConfig.showProfile field and its false default are
unchanged (data model untouched, still available if a future
account feature wires it up).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/features/project-editor/schema/editor-schema.ts

@@ -47,7 +47,6 @@ export const SECTION_FIELD_SCHEMAS: Record<ProjectEditorSectionId, readonly Fiel
     { key: 'header.showCategories', section: 'header', type: 'toggle', labelKey: 'builder.showCategories', hintKey: 'builder.showCategoriesDesc' },
     { key: 'header.showLanguages', section: 'header', type: 'toggle', labelKey: 'builder.showLanguages', hintKey: 'builder.showLanguagesDesc' },
     { key: 'header.showCart', section: 'header', type: 'toggle', labelKey: 'builder.showCart', hintKey: 'builder.showCartDesc' },
-    { key: 'header.showProfile', section: 'header', type: 'toggle', labelKey: 'builder.showProfile', hintKey: 'builder.showProfileDesc' },
     { key: 'header.showWishlist', section: 'header', type: 'toggle', labelKey: 'builder.showWishlist', hintKey: 'builder.showWishlistDesc' },
     { key: 'header.showCompare', section: 'header', type: 'toggle', labelKey: 'builder.showCompare', hintKey: 'builder.showCompareDesc' },
     { key: 'header.showRegion', section: 'header', type: 'toggle', labelKey: 'builder.showRegion', hintKey: 'builder.showRegionDesc' },