fix(domain-rer): rebuild dataset from frwiki + OSM

[Calixteair]

Summary

• Rebuild domains/rer/entities.json from scratch using the frwiki category tree (Ligne <A..E> du RER d'Île-de-France) as the canonical station list, then OSM Overpass joined on wikidata=Q... to pull the operator-facing name tag.
• Adds wiki_titles.json sidecar so fame_score_rer.py resolves frwiki titles in O(1) instead of guessing via TITLE_VARIANTS.
• Dataset 230 → 241 entities, fame_score coverage 143 → 241 (62% → 100%).

Why

The v1 ingest (scripts/ingest/build_rer_dataset.py) filtered OSM relations on network="RER" (strict equality) and member nodes on role="stop" (strict). Both filters lose every SNCF-operated portion of the network and silently drop nodes mapped with halt/station/empty roles. Visible symptoms reported: missing Saint-Germain-en-Laye, Poissy, Cergy-le-Haut, Marne-la-Vallée - Chessy, Boissy-Saint-Léger, Melun, Tournan, plus a handful of OSM-name typos (e.g. doublons "Val-de-Fontenay (RER A)" vs "Val de Fontenay").

WDQS was deliberately avoided — rate-limited to ~1 req/min since the 2024 outage, returns Wikimedia error HTML at category scale.

Diff at a glance

Metric	Before	After
Entities	230	241
Fame coverage	143	241
Phantom entries	~10	0
Dataset version	0.2.0	0.4.0

Notable changes:

• +19 real additions, -8 removals (all dedup/rename via stable QID join).
• Val de Fontenay now correctly tagged RER A + E.
• Station names corrected from OSM ground truth: "Luxembourg" (not "Le Luxembourg"), "Invalides" (not "Les Invalides"), "Avenue Foch" (not "L'avenue Foch"), etc.

Files

• scripts/ingest/build_rer_dataset_v2.py (new) — main pipeline, defaults to dry-run, --apply writes.
• scripts/ingest/fame_score_rer.py — now reads wiki_titles.json sidecar first, falls back to the previous TITLE_VARIANTS guess loop only for entities absent from the sidecar.
• domains/rer/entities.json — rebuilt (241 entities, all fame-scored).
• domains/rer/metadata.json — version 0.4.0, new dataset_sha256.
• domains/rer/wiki_titles.json (new) — {entity_id: frwiki_title} sidecar, regenerated on every --apply.

Test plan

• CI green (cargo fmt + clippy + test, pnpm typecheck + lint, gitleaks, Trivy).
• After merge: deploy via SSH ci-kalidoku → bao-deploy.sh kalidoku.
• After deploy: wipe stale RER grids in prod DB (separate ops step, prepared SQL below) so the worker regenerates with the new dataset.
• Spot-check in-game: load a fresh RER grid, confirm Saint-Germain-en-Laye / Poissy / Marne-la-Vallée-Chessy appear and accept their lines.

Follow-up (out of scope)

• zone attribute still left at 0.0 (Wikidata P5031 not used, OSM doesn't expose fare zone). A future enrichment pass would need WDQS or a manual mapping for the ~5 zone-based predicates.