refactor: hardcode API IDs and coaster lists, remove Playwright discovery

Embed Six Flags API IDs directly in the park registry and snapshot
coaster lists from park-meta.json into a TypeScript module. This
eliminates the Playwright-based discovery script, RCDB scraper, and
runtime dependency on park-meta.json — preparing for the backend
API transition.

- Add apiId field to Park type and all 24 park entries
- Create lib/coaster-data.ts with hardcoded coaster lists
- Update page components to use park.apiId and new getCoasterSet()
- Remove scripts/discover.ts, lib/scrapers/rcdb.ts, lib/park-meta.ts
- Remove data/park-meta.json from shared volume
- Remove playwright devDependency and discover npm script
- Simplify scripts/scrape.ts (no RCDB, no discovery checks)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -9,7 +9,6 @@
     "lint": "next lint",
     "scrape": "tsx scripts/scrape.ts",
     "scrape:force": "tsx scripts/scrape.ts --rescrape",
-    "discover": "tsx scripts/discover.ts",
     "debug": "tsx scripts/debug.ts",
     "test": "tsx --test tests/*.test.ts"
   },
@@ -27,7 +26,6 @@
     "@types/react-dom": "^19",
     "eslint": "^9",
     "eslint-config-next": "^15.3.0",
-    "playwright": "^1.59.1",
     "tailwindcss": "^4",
     "tsx": "^4.21.0",
     "typescript": "^5"