feat: add data integrity page with bulk parent discovery

Database maintenance dashboard at /db/:dbId/integrity showing provider
coverage gaps, missing parent links, orphaned edges, and stale data.
Includes bulk parent ID discovery with SSE progress and cancellation.

Author: atomantic

.changelog/v0.5.x.md

@@ -119,6 +119,17 @@ data/provider-cache/
 ### Dead Code Removal (v0.5.3)
 - Deleted `UnifiedPlatformSection.tsx` (superseded by ProviderDataTable)
 
+### Data Integrity Page + Bulk Discovery (v0.5.4)
+- Database maintenance dashboard at `/db/:dbId/integrity` with summary cards and tabbed interface
+- Integrity service: provider coverage gaps, parent linkage gaps, orphaned edges, stale cache detection
+- Bulk discovery service: database-wide automated parent ID discovery with SSE progress and cancellation
+- Parents tab: provider selector, "Discover All" button with real-time progress bar
+- Coverage tab: persons with incomplete provider links shown with linked/missing badges
+- Orphans tab: broken parent edges with missing person indicators
+- Stale tab: configurable age threshold with color-coded staleness
+- API endpoints at `/api/integrity/:dbId` for all checks and bulk operations
+- Sidebar nav item with ShieldCheck icon under each database
+
 ## Full Changelog
 
 **Full Diff**: https://github.com/atomantic/SparseTree/compare/v0.4.16...v0.5.0

PLAN.md

@@ -33,6 +33,7 @@ High-level project roadmap. For detailed phase documentation, see [docs/roadmap.
 | 15.13 | Provider comparison table + LinkedIn | ✅ |
 | 15.14 | Code quality refactoring | 📋 |
 | 15.16 | Ancestry photo upload | ✅ |
+| 15.17 | Data integrity + bulk discovery | ✅ |
 | 16 | Multi-platform sync architecture | 📋 |
 | 17 | Real-time event system (Socket.IO) | 📋 |
 
@@ -255,6 +256,52 @@ See [docs/architecture.md](./docs/architecture.md) for full details.
 
 ## Next Steps
 
+### Phase 15.17: Data Integrity Page + Bulk Discovery
+
+Database maintenance dashboard with automated parent ID discovery:
+
+- **Integrity Service**: `integrity.service.ts` - SQL-based checks for data quality
+  - `getIntegritySummary()` - Counts for all check types
+  - `getProviderCoverageGaps()` - Persons with some but not all provider links
+  - `getParentLinkageGaps()` - Parent edges where parent lacks provider link the child has
+  - `getOrphanedEdges()` - Parent edges referencing non-existent person records
+  - `getStaleProviderData()` - Provider cache files older than N days
+- **Bulk Discovery Service**: `bulk-discovery.service.ts` - Database-wide parent ID discovery
+  - Async generator yielding `BulkDiscoveryProgress` events for SSE streaming
+  - Deduplicates by child_id (one scrape discovers both parents)
+  - Reuses existing `parentDiscoveryService.discoverParentIds()` per child
+  - Rate limited via `PROVIDER_DEFAULTS[provider].rateLimitDefaults`
+  - In-memory cancellation via `Set<operationId>` checked between iterations
+- **API Endpoints** (`/api/integrity/:dbId`):
+  - `GET /` - Full integrity summary
+  - `GET /coverage` - Provider coverage gaps (?providers=fs,ancestry)
+  - `GET /parents` - Parent linkage gaps (?provider=familysearch)
+  - `GET /orphans` - Orphaned edges
+  - `GET /stale` - Stale records (?days=30)
+  - `POST /discover-all` - Start bulk discovery
+  - `GET /discover-all/events` - SSE stream for progress
+  - `POST /discover-all/cancel` - Cancel running operation
+- **UI**: `IntegrityPage.tsx` at `/db/:dbId/integrity`
+  - Summary cards (4 check types with counts, clickable)
+  - Tabbed interface: Parents | Coverage | Orphans | Stale
+  - Parents tab: provider selector, "Discover All" button with SSE progress bar + cancel
+  - Coverage tab: table of persons with linked/missing provider badges
+  - Orphans tab: table of broken parent edges
+  - Stale tab: configurable days threshold, table with age coloring
+  - Sidebar nav item with ShieldCheck icon
+- **Shared Types**: `IntegritySummary`, `ProviderCoverageGap`, `ParentLinkageGap`, `OrphanedEdge`, `StaleRecord`, `BulkDiscoveryProgress`
+- **Files Created**:
+  - `server/src/services/integrity.service.ts`
+  - `server/src/services/bulk-discovery.service.ts`
+  - `server/src/routes/integrity.routes.ts`
+  - `client/src/components/integrity/IntegrityPage.tsx`
+- **Files Modified**:
+  - `shared/src/index.ts` - New types
+  - `server/src/index.ts` - Route mount
+  - `client/src/services/api.ts` - API methods + type re-exports
+  - `client/src/App.tsx` - Route
+  - `client/src/components/layout/Sidebar.tsx` - Nav item
+
 ### Phase 15.14: Code Quality Refactoring (Pre-Phase 16 Cleanup)
 
 Code audit identified DRY/YAGNI/performance issues to address before Phase 16:

client/src/App.tsx

@@ -14,6 +14,7 @@ import { ReportsPage } from './pages/ReportsPage';
 import { FavoritesPage } from './components/favorites/FavoritesPage';
 import { SparseTreePage } from './components/favorites/SparseTreePage';
 import { DatabaseFavoritesPage } from './components/favorites/DatabaseFavoritesPage';
+import { IntegrityPage } from './components/integrity/IntegrityPage';
 
 function App() {
   return (
@@ -38,6 +39,7 @@ function App() {
         <Route path="favorites" element={<FavoritesPage />} />
         <Route path="favorites/sparse-tree/:dbId" element={<SparseTreePage />} />
         <Route path="db/:dbId/favorites" element={<DatabaseFavoritesPage />} />
+        <Route path="db/:dbId/integrity" element={<IntegrityPage />} />
       </Route>
     </Routes>
   );