refactor: drop AI/vision pipeline + plain Postgres + full-refresh script

Removes the OpenCLIP-on-ONNX classifier and everything that fed or
consumed it:
  - backend: app/services/vision/, app/tasks/vision.py,
    app/services/feature_flags.py, app/routers/features.py — all
    deleted; admin AI/feature-flag endpoints and the worker-vision
    bootstrap call gone. Photo.needs_review and its index dropped.
  - frontend: AI Settings tab, useFeaturesQuery hook, FeatureFlag
    types, "Needs Review" sidebar entry + filter, needs_review filter
    URL param all gone.
  - infra: worker-vision compose service + models_data volume deleted;
    worker-light command no longer runs bootstrap_models; the db
    image switches from pgvector/pgvector:pg16 to postgres:16; backend
    Dockerfile drops the dedicated torch RUN layer; requirements.txt
    drops torch/torchvision/open-clip-torch/onnxruntime.

Alembic 0019_drop_ai_remnants:
  - drops photos.needs_review + ix_photos_needs_review
  - DROP EXTENSION IF EXISTS vector (must run before the image swap;
    the new postgres:16 doesn't ship pgvector)

New scripts/full_refresh.py: one-shot DB ↔ filesystem reconciliation.
Runs cleanup_data_integrity, scans every active SourceRoot inline
(no celery dependency so the worker can be stopped), hard-prunes
photo + folder rows for files that are gone, removes orphan
/data/thumbs/{user}/{photo}/ directories. New helper
prune_orphan_thumbnails in cleanup.py.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/hooks/useBulkPhotoMutations.ts

@@ -18,7 +18,7 @@ import type { MemoriesResponse, MemoryPhoto } from '../services/api'
  *    per-photo cache so rating stars / color swatches flip instantly.
  *  - Rolls back the patch on error and surfaces a toast.
  *  - Invalidates the photo/library queries on success so server-side
- *    derived fields (needs_review, date_warning, etc.) reconcile.
+ *    derived fields (date_warning, etc.) reconcile.
  *
  * Discard lives elsewhere — its two call sites have deliberately
  * different semantics (keep-in-place for the X hotkey; strip-from-

frontend/src/hooks/useFeaturesQuery.ts

@@ -1,32 +0,0 @@
-import { useQuery, useQueryClient } from '@tanstack/react-query'
-import { features, type FeaturesMap } from '../services/api'
-
-export const FEATURES_QUERY_KEY = ['features'] as const
-
-/** Read the effective feature-flag state (admin override or YAML
- *  default). Powers conditional rendering of pipeline-dependent UI —
- *  People view, Tags view, OCR snippets, etc. */
-export function useFeaturesQuery() {
-  return useQuery<FeaturesMap>({
-    queryKey: FEATURES_QUERY_KEY,
-    queryFn: features.list,
-    // Re-read every minute so admin toggles reflect without a page
-    // reload. The admin tab also invalidates this key on write so the
-    // refresh can be immediate for the admin who just flipped it.
-    staleTime: 60_000,
-    refetchInterval: 60_000,
-  })
-}
-
-export function useIsFeatureEnabled(name: 'vision.enabled'): boolean {
-  const { data } = useFeaturesQuery()
-  // Default to enabled while loading so we don't flash "feature off"
-  // during a first-paint fetch. The backend is the source of truth;
-  // any gated UI that slipped through just returns empty data anyway.
-  if (!data) return true
-  return !!data[name]
-}
-
-export function invalidateFeaturesQuery(queryClient: ReturnType<typeof useQueryClient>) {
-  queryClient.invalidateQueries({ queryKey: FEATURES_QUERY_KEY })
-}

frontend/src/hooks/useFilterUrlSync.ts

@@ -86,7 +86,6 @@ function parseUrl(): HydratePayload {
   }
 
   if (sp.get('duplicates') === 'true') out.duplicates = true
-  if (sp.get('needs_review') === 'true') out.needsReview = true
 
   const groupBy = sp.get('group')
   if (groupBy === 'date' || groupBy === 'tag') out.groupBy = groupBy
@@ -120,7 +119,6 @@ function writeUrl(f: FilterState & { currentSection?: string }) {
   if (f.folderId) sp.set('folder_id', f.folderId)
   if (f.tagIds.length > 0) sp.set('tag_ids', f.tagIds.join(','))
   if (f.duplicates) sp.set('duplicates', 'true')
-  if (f.needsReview) sp.set('needs_review', 'true')
   if (f.groupBy !== 'date') sp.set('group', f.groupBy)
   if (f.currentSection && f.currentSection !== 'all-photos')
     sp.set('section', f.currentSection)

frontend/src/hooks/usePhotosQuery.ts

@@ -65,7 +65,6 @@ export function usePhotosQuery() {
         folderId: s.folderId,
         tagIds: s.tagIds,
         duplicates: s.duplicates,
-        needsReview: s.needsReview,
         groupBy: s.groupBy,
         sortBy: s.sortBy,
         sortOrder: s.sortOrder,