Add checkup review flags, duplicate detection, and corrected painting images.

Introduce checkup_checked/checkup_fixed on paintings with Checkup page filters and API. Fixed paintings auto-mark as reviewed. Add find-duplicates tooling and document debug/checkup workflow. Include Botticelli and Michelangelo image fixes from checkup.

Co-authored-by: Cursor <cursoragent@cursor.com>

Documentation/basics.md

@@ -36,11 +36,12 @@ Gallery/
 │   │   ├── data/movement-lineage.ts       # Curated movement predecessor links (UI)
 │   │   └── utils/timelineView.ts          # Shared zoom/pan math for timeline + movements
 │   └── dist/            # Production build (served by API when present)
-├── scripts/             # Seed, bios, catalog expansion, image fetch
+├── scripts/             # Seed, bios, catalog expansion, image fetch, checkup tools
 │   ├── fetch-artist-bios.js
 │   ├── expand-paintings.js
 │   ├── famous-paintings-data.js
 │   ├── fetch-missing-images.js
+│   ├── find-duplicate-paintings.js
 │   └── image-fetcher.js
 ├── data/images/         # Local portraits and paintings (+ thumbs/)
 ├── db/                  # SQL schema and migrations (when present)
@@ -222,6 +223,24 @@ Opened from the 3D hall (click a frame) or from influence thumbnails on another
 - **3D gallery images** use locally cached files only; slow remote fetches would break realtime rendering.
 - **Influence data** is stored as directed links from paintings to sources (another painting, an artist, or a movement), with optional period fields and citation metadata (source author, quote, URL).
 
+## Developer tools (image audit)
+
+Optional workflow for curating local image files — not part of the public visitor experience.
+
+| Feature | Where | Purpose |
+|---------|--------|---------|
+| **Debug mode** | Home header toggle (`client/src/utils/debugMode.ts`) | Persists in `localStorage`; enables debug panel on painting detail |
+| **Checkup page** | Home header → **Checkup** (`CheckupPage.tsx`) | Full-catalog table: gallery vs detail thumbnails, search, fix, review flags |
+| **Debug panel** | Painting detail (bottom-left, when debug mode on) | Google-family image search preview + **Fix it** for the current work |
+
+**Checkup columns:** Gallery and Detail thumbnails, Search (reference image), Fix (replace local file), **Reviewed** (`checkup_checked`), **Fixed** (`checkup_fixed`).
+
+**Search visible** runs image search only for rows currently shown after text/filter — not automatically on page load. Fixing an image sets **Fixed** and **Reviewed**.
+
+Run `npm run migrate:checkup-flags` once on existing databases. After server code changes, restart `npm run dev` so new routes (e.g. `PATCH …/checkup-flags`) are registered.
+
+See [API.md](API.md#developer-image-audit) and [data-and-images.md](data-and-images.md#duplicate-paintings).
+
 ## Related docs
 
 | Document | Contents |