Keep prod health checks and route fallbacks from failing on stale API entries

Add a Bun health script that exercises top-level, dynamic, and representative video routes against one or more hosts so prod regressions are visible from a single command.

Device pages now fall back to the bundled device list when the external API misses a slug, and orphaned tv slugs redirect to /benchmarks instead of returning a 500. Video fallback logic reuses the existing YouTube-to-listing builder so route reconstruction stays aligned with the current build logic.

Constraint: The external API host can lag behind the frontend build and omit per-slug JSON files that public routes still expect
Rejected: Import the generated video list directly | static/video-list.json is too large for a safe SSR fallback
Rejected: Leave missing tv routes as 500s | a stale public URL should degrade to a useful redirect instead of breaking the request
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Keep route fallbacks tied to build-time artifacts from the same repo so frontend and fallback data stay in sync
Tested: bun scripts/health http://127.0.0.1:4322; vitest ./test/prebuild/config-node.test.js ./test/prebuild/site-listings.test.js; pnpm run netlify-build
Not-tested: live production deploy before push

helpers/site-listings.js

@@ -0,0 +1,47 @@
+import fs from 'fs-extra'
+import path from 'path'
+import { fileURLToPath } from 'url'
+
+import {
+    buildVideoListingFromFetchedVideo,
+    makeVideoSlug
+} from '~/helpers/build-video-list.js'
+import { youtubeVideoPath } from '~/helpers/api/youtube/build.js'
+
+const currentModuleDirectory = path.dirname( fileURLToPath( import.meta.url ) )
+const appListPath = path.join( currentModuleDirectory, '../static/app-list.json' )
+const gameListPath = path.join( currentModuleDirectory, '../static/game-list.json' )
+const deviceListPath = path.join( currentModuleDirectory, '../static/device-list.json' )
+const trailingCommaPattern = /,\s*([\]}])/g
+
+function parseGeneratedJsonFile ( filePath ) {
+    const fileContents = fs.readFileSync( filePath, 'utf8' )
+
+    return JSON.parse( fileContents.replace( trailingCommaPattern, '$1' ) )
+}
+
+export function getDeviceListingBySlug ( slug ) {
+    const deviceList = parseGeneratedJsonFile( deviceListPath )
+
+    return deviceList.find( device => device.slug === slug ) || null
+}
+
+function getAllVideoAppsList () {
+    return [
+        ...parseGeneratedJsonFile( appListPath ),
+        ...parseGeneratedJsonFile( gameListPath )
+    ]
+}
+
+export async function getVideoListingBySlug ( slug ) {
+    const fetchedVideos = await fs.readJson( youtubeVideoPath )
+    const allVideoAppsList = getAllVideoAppsList()
+
+    for ( const [ videoId, fetchedVideo ] of Object.entries( fetchedVideos ) ) {
+        if ( makeVideoSlug( fetchedVideo.title, videoId ) !== slug ) continue
+
+        return await buildVideoListingFromFetchedVideo( fetchedVideo, videoId, allVideoAppsList )
+    }
+
+    return null
+}