chore: keep reference photography local and out of the repository

Reference images are development-only material: licensing is not a gate for
local private use, so they are simply never committed. Art/reference/ is now
gitignored; the licensed status of anything shipped is still recorded in
THIRD_PARTY_NOTICES.md.

Adds Tools/commons_fetch.py, which fetches Wikimedia Commons imagery by search
or exact title and writes a provenance sidecar, plus Docs/reference-notes-hollywood.md
recording what each local set is evidence for.

THIRD_PARTY_NOTICES.md

@@ -25,26 +25,23 @@ Status values: **verified** (licence confirmed and permits our use), **pending**
 
 Attribution string for any OSM-derived output: "© OpenStreetMap contributors", <https://www.openstreetmap.org/copyright>.
 
-## Reference photography (development only, not shipped)
+## Reference photography (local only, not committed, not shipped)
 
-Committed in `Art/reference/hollywood/` (Git LFS). Copied 2026-11-06 from `…/06-games/security-game/docs/screens/refs/hollywood/`, which holds the per-file provenance in `SIDECAR.md` — carried over verbatim with the images. These are development evidence and are not built into the game.
+Reference photographs are **not** part of this repository. They live in the gitignored `Art/reference/` tree on the development machine, are used only for internal, private development, and are never built into a build or shipped. `.gitignore` enforces this; nothing under `Art/reference/` may be added, staged, or committed.
 
-| File | Subject | Author | Licence | Shipped |
-| --- | --- | --- | --- | --- |
-| `el-capitan-facade-day-wikimedia-2009-10-27.jpg` | El Capitan facade, day | woo | CC BY 2.0 | no |
-| `el-capitan-theatre-blade-sign-day-wikimedia-2008-10.jpg` | blade sign and temple frontage | Andreas Praefcke | CC BY 3.0 | no |
-| `el-capitan-theatre-marquee-neighbour-day-wikimedia-2009-07-11.jpg` | east neighbour marquee | Alan Light | CC BY 2.0 | no |
-| `premiere-staging-street-day-wikimedia-2006-02-12.jpg` | premiere staging | John Barreiros | CC BY 2.0 | no |
-| `masonic-temple-historic-pd-1922.jpg` | Masonic Temple, 1922 | Charles W. Beam | public domain | no |
-| `ovation-hollywood-across-street-pd-2006-12-28.jpg` | Ovation Hollywood, across street | Gary Minnaert | public domain | no |
-| `walk-of-fame-terrazzo-ovation-day-cc0-2019-06-20.jpg` | Walk of Fame terrazzo band | Luijtenphotos | CC0 | no |
-| `walk-of-fame-star-closeup-cc0-2022-07-08.jpg` | star close-up | Benoît Prieur | CC0 | no |
-| `hollywood-boulevard-night-context-ccbysa.jpg` | boulevard at night (near Vine) | Downtowngal | CC BY-SA 3.0 | no |
+| Local folder | Source | Provenance |
+| --- | --- | --- |
+| `Art/reference/hollywood/` | Copied 2026-11-06 from `…/06-games/security-game/docs/screens/refs/hollywood/` | That folder's `SIDECAR.md` (author, licence, URL, crop notes) |
+| `Art/reference/north-chinese/` | Fetched 2026-11-06 with `Tools/commons_fetch.py` from the Wikimedia Commons API | `sidecar.json` in the folder |
+| `Art/reference/north-tussauds/` | Same | `sidecar.json` in the folder |
 
-Notes:
-- The CC BY-SA frame is used for colour and lighting study only. No texture, mesh, or material is derived from it. Any future derivative needs a fresh share-alike review before use.
-- Pre-existing crop and redaction notes live in the sidecar and apply to any reuse.
-- These photos are evidence for proportions, signage, and staging. They are licensed as photographs, not as building designs; do not treat them as permission to reproduce signage artwork at full fidelity. Venue lettering and trademarks are separate rights.
+What the images are used for, what they are evidence for, and the block's recorded measurements live in [Docs/reference-notes-hollywood.md](Docs/reference-notes-hollywood.md). That document is committed; the images are not.
+
+Rules that still apply, because they are about shipped output rather than local working material:
+
+- No reference photograph may be shipped, baked into a texture, or distributed. If a shipped asset would otherwise derive from one, that is a licensing decision to be made before the release, recorded here.
+- Venue lettering, signage artwork, and trademarks are separate rights from the photograph. Copying a façade's proportions is not the same as reproducing its signage.
+- A reference image whose provenance cannot be found locally must not be used at all.
 
 ## Assets