refactor(apps): 主题系统迁移至 ColorScheme + 扩展架构并支持 Dark Mode

apps/AGENTS.md

@@ -16,9 +16,11 @@ This file governs `apps/**` (Flutter). Keep rules strict, short, and reusable.
 
 ## UI Design System (Must)
 
-- Use design tokens only from `apps/lib/core/theme/design_tokens.dart` (`AppColors`, `AppSpacing`, `AppRadius`).
-- No hardcoded visual values.
-- If semantics are missing, add token definitions first.
+- **Semantic colors**: always use `Theme.of(context).colorScheme.*` (primary, surface, error, etc.). Never hardcode hex or `Colors.*`.
+- **Brand palette colors** (event presets, avatar colors, Eisenhower matrix quadrants): use `Theme.of(context).extension<AppColorPalette>()!.*`.
+- **Spacing / Radius**: use `AppSpacing` / `AppRadius` from `design_tokens.dart`. No hardcoded values.
+- `AppTheme.light` / `AppTheme.dark` provide complete `ColorScheme` (light + dark). `MaterialApp` wires them via `theme:` / `darkTheme:`.
+- If a semantic slot is missing from `ColorScheme`, add it to `AppTheme` — do not bypass `colorScheme` with hardcoded values.
 
 ## Reuse & Composition (Must)
 
@@ -63,6 +65,9 @@ This file governs `apps/**` (Flutter). Keep rules strict, short, and reusable.
 
 - Reads/writes that affect consistency must go through repository layer.
 - Cache keys and invalidation policy belong to repository, not UI/Bloc.
+- Shared cache infrastructure must live under `apps/lib/data/cache/`; feature modules must not duplicate low-level cache store logic.
+- Cross-feature data access must go through `apps/lib/data/repositories/`; do not import another feature's data implementation directly from UI/Bloc.
+- Repository instances should be resolved from DI singletons to reuse cache and avoid per-feature re-creation.
 
 ## Testing Policy