docs(02-04): execution summary and state update

- 02-04-SUMMARY.md: admin API plan complete (18 tests, 7 endpoints, all security checks pass)
- STATE.md: advanced to plan 4/5, updated metrics and session continuity

.planning/STATE.md

@@ -4,13 +4,13 @@ milestone: v1.0
 milestone_name: milestone
 current_phase: 2
 status: in_progress
-last_updated: "2026-05-22T17:55:55Z"
+last_updated: "2026-05-22T18:06:00Z"
 progress:
   total_phases: 5
   completed_phases: 1
   total_plans: 10
-  completed_plans: 8
+  completed_plans: 9
-  percent: 30
+  percent: 34
 ---
 
 # Project State
@@ -25,7 +25,7 @@ progress:
 | Phase | Name | Status |
 |---|---|---|
 | 1 | Infrastructure Foundation | ✓ Complete |
-| 2 | Users & Authentication | In Progress (3/5 plans complete) |
+| 2 | Users & Authentication | In Progress (4/5 plans complete) |
 | 3 | Document Migration & Multi-User Isolation | Not Started |
 | 4 | Folders, Sharing, Quotas & Document UX | Not Started |
 | 5 | Cloud Storage Backends | Not Started |
@@ -33,8 +33,8 @@ progress:
 ## Current Position
 
 **Phase:** 02-users-authentication — In Progress
-**Plan:** 3/5 complete (Plan 03: TOTP enrollment + password reset + account management UI)
+**Plan:** 4/5 complete (Plan 04: Admin backend API)
-**Progress:** ███░░░░░░░ 30% (1/5 phases + 3/5 Phase 2 plans)
+**Progress:** ████░░░░░░ 34% (1/5 phases + 4/5 Phase 2 plans)
 
 ## Performance Metrics
 
@@ -43,7 +43,7 @@ progress:
 | Phases complete | 1 / 5 |
 | Requirements mapped | 54 / 54 |
 | Plans written | 5 (Phase 1) |
-| Plans complete | 8 (5 Phase 1 + 3 Phase 2) |
+| Plans complete | 9 (5 Phase 1 + 4 Phase 2) |
 
 ## Accumulated Context
 
@@ -79,6 +79,9 @@ progress:
 | Deferred Celery import in /password-reset | send_reset_email.delay called via from tasks.email_tasks import send_reset_email inside handler body — same circular-import fix as document_tasks |
 | TOTP QR code as otpauth:// link | No QR library installed; plan permits manual secret display for MVP; functional flow complete without rendered QR image |
 | ConfirmBlock no acknowledgment checkbox | ConfirmBlock handles message + button pair; BackupCodesDisplay owns its separate acknowledgment checkbox — no overlap |
+| ADMIN-07 enforced by omission | No impersonation endpoint exists; AST check + test_admin_impersonation_not_found verify absence; violates privacy-first core value |
+| _user_to_dict() whitelist for admin responses | Explicit field whitelist prevents accidental password_hash/credentials_enc leakage from admin endpoints |
+| Quota warning is 200 not 4xx | Below-usage limit change is applied; warning=True advisory field returned — not a rejection |
 
 ### Open Questions
 
@@ -97,6 +100,6 @@ _Updated at each phase transition._
 
 | Field | Value |
 |---|---|
-| Last session | 2026-05-22 — Executed Phase 2 Plan 03 (TOTP enrollment + password reset + account management UI) |
+| Last session | 2026-05-22 — Executed Phase 2 Plan 04 (Admin backend API: user CRUD, quota, AI config) |
-| Next action | Run `/gsd:execute-phase 2` to continue Phase 2 (Plan 04: admin endpoints) |
+| Next action | Run `/gsd:execute-phase 2` to continue Phase 2 (Plan 05: admin panel frontend) |
 | Pending decisions | See Open Questions above |

.planning/phases/02-users-authentication/02-04-SUMMARY.md

@@ -0,0 +1,165 @@
+---
+phase: 02-users-authentication
+plan: 04
+subsystem: auth
+tags: [fastapi, admin, user-management, quota, ai-config, tdd, security, role-based-access]
+
+# Dependency graph
+requires:
+  - phase: 02-users-authentication
+    plan: 02
+    provides: "backend/api/auth.py (auth router, limiter), deps/auth.py (get_current_admin), services/auth.py (hash_password, revoke_all_refresh_tokens, create_password_reset_token)"
+  - phase: 02-users-authentication
+    plan: 03
+    provides: "backend/config.py: frontend_url setting for reset link construction, tasks/email_tasks.py: send_reset_email.delay pattern"
+provides:
+  - "backend/api/admin.py: GET /api/admin/users, POST /api/admin/users, PATCH /api/admin/users/{id}/status, POST /api/admin/users/{id}/password-reset, GET /api/admin/users/{id}/quota, PATCH /api/admin/users/{id}/quota, PATCH /api/admin/users/{id}/ai-config"
+  - "backend/tests/test_admin_api.py: 18 tests covering all admin endpoints (role enforcement, password_must_change, no impersonation, quota warning, AI config)"
+affects: [02-05, 03-user-document-isolation, 04-folders-sharing-quotas]
+
+# Tech tracking
+tech-stack:
+  added: []  # No new packages — all dependencies established in Plans 01/02
+  patterns:
+    - "get_current_admin Depends() on every handler — no handler uses get_current_user alone (SEC-07)"
+    - "_user_to_dict() whitelist helper — explicitly enumerates safe fields; password_hash/credentials_enc excluded by construction"
+    - "password_must_change=True on admin-created users — forced password change on first login (ADMIN-01)"
+    - "Sole-admin deactivation guard — counts active admins before applying deactivation; raises 400 if count would reach 0 (T-02-29)"
+    - "Celery email dispatch with deferred import — send_reset_email.delay inside handler body to avoid circular imports"
+    - "Quota warning — 200 OK with warning=True when new limit_bytes < used_bytes; change still applies"
+    - "field_validator on UserCreate.password and QuotaUpdate.limit_bytes — Pydantic v2 style; raises 422 on invalid input"
+
+key-files:
+  created:
+    - "backend/api/admin.py — 7 admin endpoints with get_current_admin on every handler"
+    - "backend/tests/test_admin_api.py — 18 tests: list/create/deactivate/reset/quota/AI-config/no-impersonation/no-password_hash"
+  modified:
+    - "backend/main.py — added admin_router include after auth_router"
+
+key-decisions:
+  - "ADMIN-07 enforced by omission: no impersonation route exists; verified by AST check and test_admin_impersonation_not_found"
+  - "password_hash only appears in admin.py at line 186 (User constructor for DB write, not response); _user_to_dict() whitelist prevents any leakage"
+  - "Celery mock in test_password_reset_initiates_email to avoid Redis connection in unit tests — patch targets tasks.email_tasks.send_reset_email.delay"
+  - "Sole-admin guard uses COUNT query on (role='admin', is_active=True) — prevents lockout scenario (T-02-29)"
+
+patterns-established:
+  - "Admin router pattern: APIRouter(prefix='/api/admin') + get_current_admin Depends() on every handler"
+  - "Safe response helper pattern: _user_to_dict() whitelist — use for any multi-field User response"
+  - "Quota warning pattern: return 200 with warning=True field rather than error — change is applied, caller informed"
+
+requirements-completed: [ADMIN-01, ADMIN-02, ADMIN-03, ADMIN-04, ADMIN-05, ADMIN-07, SEC-07]
+
+# Metrics
+duration: ~8min
+completed: 2026-05-22
+---
+
+# Phase 2 Plan 04: Admin Backend API Summary
+
+**7-endpoint admin API (user CRUD, quota management, AI provider assignment) with get_current_admin on every handler, _user_to_dict whitelist, password_must_change=True on create, and no impersonation endpoint**
+
+## Performance
+
+- **Duration:** ~8 min
+- **Started:** 2026-05-22T17:58:00Z
+- **Completed:** 2026-05-22T18:06:00Z
+- **Tasks:** 2 (both TDD — Task 1: admin.py, Task 2: test file)
+- **Files created:** 2, Files modified: 1
+
+## Accomplishments
+
+- All 7 admin endpoints implemented in `backend/api/admin.py` with `get_current_admin` on every handler (SEC-07)
+- Admin-created users have `password_must_change=True` — forced password change on first login (ADMIN-01, T-02-32)
+- `_user_to_dict()` whitelist helper explicitly enumerates safe response fields; `password_hash` and `credentials_enc` are excluded by construction (T-02-27)
+- Sole-admin deactivation guard: raises 400 if deactivating the only active admin (T-02-29)
+- Password reset via Celery email dispatch — does not return a token, does not impersonate (T-02-30, ADMIN-07)
+- Quota warning: 200 OK + `warning=True` when new `limit_bytes` < `used_bytes`; change is applied (ADMIN-04)
+- 18 tests passing: role enforcement, create/deactivate/reset/quota/AI-config, no impersonation route, no password_hash in responses
+- No impersonation endpoint — ADMIN-07 verified by AST check and dedicated test
+
+## Task Commits
+
+1. **Task 1 RED — test file:** `cbad9ac` (test: RED phase admin tests)
+2. **Task 1 GREEN — admin.py + main.py:** `f94e8d8` (feat: admin API endpoints)
+
+## Files Created/Modified
+
+- `backend/api/admin.py` — 7 admin endpoints; `_user_to_dict()` helper; `_validate_password_strength()`; no impersonation code
+- `backend/tests/test_admin_api.py` — 18 tests: list/create/deactivate/reset/quota/AI-config, sole-admin guard, impersonation 404, password_hash absent from responses
+- `backend/main.py` — added `from api.admin import router as admin_router` + `app.include_router(admin_router)`
+
+## Decisions Made
+
+- **ADMIN-07 by omission**: No `/impersonate` or `/login-as` route. Verified by AST walk checking for `impersonate`/`login_as` string in dump — returns zero matches. `test_admin_impersonation_not_found` asserts 404/422 for `/api/admin/users/impersonate`
+- **`password_hash` appears 3 times in admin.py** — lines 55 and 141 are doc comments; line 186 is `password_hash=hash_password(body.password)` in the User constructor (DB write, not API response). `_user_to_dict()` never includes `password_hash` in its whitelist
+- **Celery mock in tests**: `patch("tasks.email_tasks.send_reset_email.delay")` used in `test_password_reset_initiates_email` to avoid Redis connection attempt in unit tests — same mock-target pattern as Plan 03 deviation fix
+- **Quota warning is 200 not 4xx**: The plan spec says "still apply the update" and return `warning=True`. This is correct — it's an advisory, not a rejection
+
+## Deviations from Plan
+
+### Auto-fixed Issues
+
+**1. [Rule 1 - Test Fix] Celery task causes Redis connection attempt in unit test**
+- **Found during:** Task 1 (GREEN phase — first test run)
+- **Issue:** `test_password_reset_initiates_email` called the real `send_reset_email.delay()` which triggered Celery trying to connect to Redis (not available in unit tests), causing a RuntimeError after 20 retry attempts
+- **Fix:** Added `unittest.mock.patch("tasks.email_tasks.send_reset_email.delay")` context manager in the test; also added assertions that `mock_delay.call_args[0][0] == target.email` (correct address) and `"token=" in call_args[1]` (reset link contains token)
+- **Files modified:** `backend/tests/test_admin_api.py`
+- **Verification:** All 18 tests pass in 1.5s without Redis
+- **Committed in:** `f94e8d8` (GREEN phase commit)
+
+---
+
+**Total deviations:** 1 auto-fixed (Rule 1 — test Celery mock)
+**Impact on plan:** Single test-level fix — identical to the Celery mock fix pattern established in Plan 03. No implementation changes. No scope creep.
+
+## Issues Encountered
+
+None beyond the Celery mock deviation above. All implementation proceeded cleanly.
+
+## Known Stubs
+
+None — all 7 endpoints are fully implemented and returning correct data.
+
+## Threat Flags
+
+All STRIDE mitigations from the plan's threat model are implemented:
+- T-02-26: `get_current_admin` Depends() on every handler — grep count = 10 (7 handlers + 3 in helper pattern references)
+- T-02-27: `_user_to_dict()` whitelist — never includes `password_hash`, `credentials_enc`, or document content
+- T-02-28: No impersonation endpoint — AST check + `test_admin_impersonation_not_found` asserts 404/422
+- T-02-29: Sole-admin guard — COUNT query before deactivation; `test_cannot_deactivate_only_admin` asserts 400
+- T-02-30: Password reset endpoint returns 202 + message, not a token; `send_reset_email.delay` goes to user's inbox
+- T-02-31: Quota endpoint accepted as admin-visible operational data — no PII, no document content
+- T-02-32: `password_must_change=True` set in `POST /api/admin/users`; `test_create_user_sets_password_must_change` verifies DB state
+
+No new threat surface beyond what was planned.
+
+## Next Phase Readiness
+
+- All 7 admin endpoints operational with correct auth enforcement
+- Plan 02-05 (admin panel frontend) can wire to real endpoints
+- `password_must_change` flag respected by login flow (Plan 02) — admin-created users are forced to set new password on first login
+- All 53 auth + admin tests passing
+
+---
+
+## Self-Check: PASSED
+
+**Files verified:**
+
+- `backend/api/admin.py` — FOUND, contains `/api/admin/users` route
+- `backend/tests/test_admin_api.py` — FOUND (18 tests passing)
+- `backend/main.py` — FOUND, contains `admin_router`
+
+**Commits verified:**
+
+- `cbad9ac` (test: RED phase) — verified in git log
+- `f94e8d8` (feat: admin API) — verified in git log
+
+**Test results:** 18 passed (test_admin_api.py), 53 passed (all auth + admin tests combined)
+**grep -c get_current_admin backend/api/admin.py:** 10 (at least 7 required)
+**grep -c password_must_change backend/api/admin.py:** 4 (at least 1 required)
+**grep -c impersonate backend/api/admin.py:** 0 (required)
+
+---
+*Phase: 02-users-authentication*
+*Completed: 2026-05-22*