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+---
+phase: 25-file-system
+plan: 05
+subsystem: api, ui
+tags: [chat-files, file-promotion, drizzle, express, react]
+
+# Dependency graph
+requires:
+  - phase: 25-01
+    provides: chatFileService and chatFileRoutes with existing DB schema (projectId nullable FK on chatFiles)
+provides:
+  - PATCH /files/:fileId/promote endpoint that sets projectId on a chat file
+  - promoteToProject service method on chatFileService
+  - ChatFileCard promote button with FolderUp icon and onPromoted callback
+  - promoteFile API client method in chatApi
+affects: [ui-chat, chat-file-display, project-integration]
+
+# Tech tracking
+tech-stack:
+  added: []
+  patterns:
+    - "Route ordering: specific sub-routes (/files/:fileId/promote) registered before catch-all (/files/:fileId) in Express"
+    - "Optional promote callback pattern: file.projectId === null && projectId && onPromoted guards UI button render"
+
+key-files:
+  created: []
+  modified:
+    - server/src/services/chat-files.ts
+    - server/src/routes/chat-files.ts
+    - ui/src/api/chat.ts
+    - ui/src/components/ChatFileCard.tsx
+    - .planning/REQUIREMENTS.md
+
+key-decisions:
+  - "PATCH /files/:fileId/promote registered before PATCH /files/:fileId in Express router to prevent route shadowing"
+  - "promoteToProject returns null (not throws) when row missing — route handles 404 explicitly"
+  - "Promote button gated on file.projectId === null AND projectId AND onPromoted — all three required for intent"
+
+patterns-established:
+  - "Sub-route ordering: register /files/:fileId/promote before /files/:fileId"
+  - "Optional promote UX: ChatFileCard accepts optional projectId + onPromoted; renders button only when both provided and file not yet promoted"
+
+requirements-completed: [FILE-12]
+
+# Metrics
+duration: 8min
+completed: 2026-04-01
+---
+
+# Phase 25 Plan 05: File Scope Promotion Summary
+
+**PATCH /files/:fileId/promote endpoint and ChatFileCard promote button with FolderUp icon wired to chatApi.promoteFile**
+
+## Performance
+
+- **Duration:** ~8 min
+- **Started:** 2026-04-01T23:56:00Z
+- **Completed:** 2026-04-01T23:59:00Z
+- **Tasks:** 2
+- **Files modified:** 4 + REQUIREMENTS.md
+
+## Accomplishments
+- Added `promoteToProject(fileId, projectId)` method to `chatFileService` — updates `projectId` column via Drizzle ORM
+- Added `PATCH /files/:fileId/promote` Express route before generic `PATCH /files/:fileId` to prevent shadowing
+- Added `promoteFile(fileId, projectId)` to `chatApi` in `ui/src/api/chat.ts` with `ChatFile` return type
+- Added promote button to `ChatFileCard` with `FolderUp` icon, optional `projectId` and `onPromoted` props, and loading state
+- Marked FILE-12 Complete in REQUIREMENTS.md (checkbox + traceability table)
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Add promoteToProject service method and API endpoint** - `c435655f` (feat)
+2. **Task 2: Add promote button to ChatFileCard and API client method** - `4c5deb4c` (feat)
+3. **REQUIREMENTS.md update** - `9a911040` (feat, in main repo)
+
+## Files Created/Modified
+- `server/src/services/chat-files.ts` - Added `promoteToProject(fileId, projectId)` method
+- `server/src/routes/chat-files.ts` - Added `PATCH /files/:fileId/promote` route before generic PATCH route
+- `ui/src/api/chat.ts` - Added `ChatFile` import and `promoteFile(fileId, projectId)` method to `chatApi`
+- `ui/src/components/ChatFileCard.tsx` - Added `projectId?`, `onPromoted?` props, `promoting` state, `FolderUp` button
+- `.planning/REQUIREMENTS.md` - FILE-12 marked `[x]` and `Complete` in traceability table
+
+## Decisions Made
+- Registered `/files/:fileId/promote` BEFORE `/files/:fileId` in Express router to prevent the generic catch-all from capturing promote requests
+- `promoteToProject` returns `null` (not throws) when no rows returned, so the route can send an explicit 404
+- Promote button only renders when all three conditions are true: `file.projectId === null`, `projectId` prop provided, `onPromoted` prop provided — clean opt-in pattern for callers
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+None.
+
+## Known Stubs
+None — `promoteFile` calls the real API endpoint. `ChatFileCard` renders the button conditionally based on real `file.projectId` field.
+
+## User Setup Required
+None - no external service configuration required.
+
+## Next Phase Readiness
+- FILE-12 is complete: chat-scoped files can be promoted to project scope via UI
+- Callers of `ChatFileCard` (e.g. `ChatFilePreview`, `ChatMessage`) can now pass `projectId` and `onPromoted` to enable the promote affordance contextually
+- No blockers for subsequent plans
+
+## Self-Check: PASSED
+
+All files verified present. Commits c435655f and 4c5deb4c confirmed in git log.
+
+---
+*Phase: 25-file-system*
+*Completed: 2026-04-01*