phase-1: scaffold platform foundation structure and architecture governance

docs/architecture/foundation/Coding-Standards.md

@@ -0,0 +1,44 @@
+# Coding Standards
+
+Status: Mandatory
+Date: 2026-07-03
+
+## Core Principles
+
+- Keep modules small and cohesive.
+- Prefer pure functions where possible.
+- Prefer composition over inheritance.
+- Prefer configuration over conditionals.
+- Avoid duplication; extract shared behavior above 70 percent overlap.
+
+## Type Safety
+
+- No any in domain and configuration contracts.
+- Strict typing for API payloads and configuration schemas.
+- Use discriminated unions for widget and section types.
+
+## Error Handling
+
+- Errors normalized at service/integration boundaries.
+- UI displays user-safe messages from facades/view models.
+- No unhandled promise rejections.
+
+## API and IO
+
+- IO is performed in services/integrations only.
+- Use facades to orchestrate calls and map outputs.
+- Keep presentation layer side-effect free.
+
+## Testing Expectations
+
+- Unit tests for facades, services, and mapping logic.
+- Contract tests for bootstrap schema compatibility.
+- Boundary tests for forbidden imports.
+
+## Review Checklist
+
+- Does this code violate layer boundaries?
+- Is tenant behavior configuration-driven?
+- Is logic duplicated and extractable?
+- Are auth/payment contracts unchanged?
+- Is the app still compilable?