music: 30-min per-request idle timeout for reindex/manifest (from-scratch builds)

A from-scratch rebuild holds the triggering request open for many minutes with
no bytes flowing, so both server hops' idle timeouts would drop it. Bun caps the
server-level idleTimeout at 255s, but server.timeout(req, seconds) allows more
per-request:
- sidecar Bun.serve: extend /reindex, /manifest, /reindex/stream to 1800s.
- platform proxy (music router): same, via the Bun server exposed as Hono's env.

Baseline idleTimeouts unchanged (sidecar 255, main server 60). The build always
completed in the background regardless; this keeps the request itself alive.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/servers/api/music/router.ts

@@ -90,6 +90,18 @@ musicRouter.all('/*', async (ctx) => {
   const subpath = url.pathname.slice(PREFIX.length) || '/';
   const target = `${baseUrl}${subpath}${url.search}`;
 
+  // A from-scratch reindex holds this proxied connection open for minutes with no bytes flowing, which
+  // the main server's 60s idle timeout would drop. Extend it to 30 min for the build/progress endpoints
+  // (Bun passes the server as Hono's env). Matches the sidecar's own per-request extension.
+  if (subpath === '/reindex' || subpath === '/manifest' || subpath === '/reindex/stream') {
+    const server = ctx.env as { timeout?: (req: Request, seconds: number) => void } | undefined;
+    try {
+      server?.timeout?.(ctx.req.raw, 1800);
+    } catch {
+      /* older Bun / no per-request timeout — the build still completes in the background */
+    }
+  }
+
   const range = ctx.req.header('range');
   let upstream: Response;
   try {