docs: Update test coverage statistics after adding 5 auth service tests

Updated implementation-gaps.md to reflect new test coverage:
- Backend unit tests: 4,140 lines (was 2,863)
- Test cases: 217 (was 136)
- Service coverage: 46% (12/26 services, was 27%)
- Total test lines: 5,345 (unit + integration, was 4,068)

New test files added:
- mfa.service.spec.ts (477 lines, 28 tests)
- biometric-auth.service.spec.ts (287 lines, 18 tests)
- session.service.spec.ts (237 lines, 16 tests)
- device-trust.service.spec.ts (134 lines, 10 tests)
- password-reset.service.spec.ts (142 lines, 9 tests)

Remaining: 14 services still need tests (email verification, analytics,
notifications, photo, voice, feedback, etc.)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docs/implementation-gaps.md

@@ -758,8 +758,8 @@ This document identifies features specified in the documentation that are not ye
 #### Completed Features ✅
 
 1. **Backend Unit Test Suite** ✅ PARTIALLY COMPLETED
-   - Status: **27% service coverage** (7/26 services tested)
+   - Status: **46% service coverage** (12/26 services tested)
-   - Current: 2,863 lines of tests across 8 test files
+   - Current: 4,140 lines of tests across 13 test files
    - Implemented:
      * ai-safety.service.spec.ts (343 lines, 31 tests) ✅
      * ai.service.spec.ts (488 lines)
@@ -769,12 +769,17 @@ This document identifies features specified in the documentation that are not ye
      * children.service.spec.ts (378 lines)
      * tracking.service.spec.ts (421 lines)
      * app.controller.spec.ts (22 lines)
+     * **mfa.service.spec.ts (477 lines, 28 tests)** ✅ NEW (October 2025)
+     * **biometric-auth.service.spec.ts (287 lines, 18 tests)** ✅ NEW (October 2025)
+     * **session.service.spec.ts (237 lines, 16 tests)** ✅ NEW (October 2025)
+     * **device-trust.service.spec.ts (134 lines, 10 tests)** ✅ NEW (October 2025)
+     * **password-reset.service.spec.ts (142 lines, 9 tests)** ✅ NEW (October 2025)
    - Test Statistics:
-     * **136 test cases** (it() blocks)
+     * **217 test cases** (it() blocks)
-     * **57 test suites** (describe() blocks)
+     * **72 test suites** (describe() blocks)
    - Priority: High
    - Impact: Code quality and reliability
-   - **Remaining:** 19/26 services still need tests (MFA, biometric, sessions, devices, password reset, email verification, analytics, notifications, photo, voice, feedback, etc.)
+   - **Remaining:** 14/26 services still need tests (email verification, analytics, notifications, photo, voice, feedback, etc.)
    - **Target:** 80% code coverage
 
 2. **Backend Integration Tests (E2E)** ✅ PARTIALLY COMPLETED
@@ -1325,14 +1330,15 @@ This document identifies features specified in the documentation that are not ye
    - **COPPA/GDPR Compliance** (October 2): Data export, account deletion, age verification, consent management
    - **Redux Persist** (October 2): Full state persistence with localStorage, PersistGate integration
    - **Security Settings UI** (October 2): 1,748 lines - MFA, biometric auth, sessions, devices, data export, account deletion (6 components)
-   - **Backend Unit Tests** (October 2): 2,863 lines - 7/26 services tested (27% coverage), 136 test cases, 57 test suites
+   - **Backend Unit Tests** (October 2): 4,140 lines - 12/26 services tested (46% coverage), 217 test cases, 72 test suites
+     * Added 5 high-priority auth service tests (1,277 lines, 81 tests): MFA, biometric auth, sessions, device trust, password reset
    - **Backend Integration Tests** (October 2): 1,205 lines - 4 modules tested (auth, tracking, children, app), 61 test cases, 21 test suites
 
-3. **Missing Critical Features**: Testing infrastructure needs expansion (currently 27% backend service coverage, target 80% with integration/E2E tests).
+3. **Missing Critical Features**: Testing infrastructure needs expansion (currently 46% backend service coverage, target 80% with integration/E2E tests).
 
 4. **AI Implementation**: ✅ Core AI features complete (safety, rate limiting, prompt protection). Still needs context management and multi-language support.
 
-5. **Testing Progress**: Strong foundation with 4,068 lines of tests (unit + integration), 197 test cases total. Backend: 27% service coverage (7/26), 4 integration test modules. Need: 19 more service tests + 8 more integration modules.
+5. **Testing Progress**: Strong foundation with 5,345 lines of tests (unit + integration), 278 test cases total. Backend: 46% service coverage (12/26), 4 integration test modules. Need: 14 more service tests + 8 more integration modules.
 
 6. **Accessibility Gaps**: No evidence of accessibility testing or screen reader support.
 
@@ -1343,7 +1349,7 @@ This document identifies features specified in the documentation that are not ye
 1. ~~**Implement compliance features**~~ - ✅ COMPLETED (COPPA/GDPR data export/deletion, consent management, age verification)
 2. ~~**Configure Redux Persist**~~ - ✅ COMPLETED (State persists with localStorage, PersistGate integration)
 3. ~~**Frontend UI for auth/compliance features**~~ - ✅ COMPLETED (MFA, biometric, sessions, devices, data export, account deletion - 1,748 lines)
-4. **Expand test coverage** - Currently 4,068 lines of tests (197 test cases: 136 unit + 61 integration). Backend: 27% service coverage (7/26). Need: 19 more service tests (high-priority: MFA, biometric, sessions, devices, password reset), frontend E2E tests, CI/CD integration. Target: 80% coverage
+4. **Expand test coverage** - Currently 5,345 lines of tests (278 test cases: 217 unit + 61 integration). Backend: 46% service coverage (12/26). Need: 14 more service tests (email verification, analytics, notifications, photo, voice, feedback, etc.), frontend E2E tests, CI/CD integration. Target: 80% coverage
 5. **Add accessibility features** - Legal requirement and good practice (WCAG AA compliance, screen readers, keyboard nav)
 
 ### Documentation Quality