feat(backend,frontend): migrate data APIs from REST to native tRPC over WebSocket

Replace REST module routers with a single typed tRPC appRouter served over
/trpc (HTTP + WebSocket), and rewire the frontend to call it via
@trpc/client wsLink (browser) and httpLink (RSC data layer). Existing
/api/health + /api/metrics stay as plain Express for infra scraping.

Notable fixes surfaced by the live smoke test:
- Express 5 / path-to-regexp v8 rejects the /trpc/* wildcard route; use a
  prefix middleware that computes opts.path from the URL instead.
- nodeHTTPRequestHandler treats opts.path as the literal procedure path, so
  it is derived per-request from req.url.
- Two ws servers on one http.Server (the /ws voice socket + /trpc) collided
  and returned 400 on upgrade; both now use noServer + a manually routed
  server.on('upgrade') keyed by path.

Verified: BE tsc+biome+40 vitest green; FE tsc+biome green; live
HTTP and WebSocket calls returned real prod data.

Co-Authored-By: Claude Opus 4.5 (1M context) <noreply@anthropic.com>

services/frontend/pnpm-lock.yaml

@@ -8,6 +8,9 @@ importers:
 
   .:
     dependencies:
+      '@trpc/client':
+        specifier: ^11.18.0
+        version: 11.18.0(@trpc/server@11.18.0(typescript@5.9.3))(typescript@5.9.3)
       clsx:
         specifier: ^2.1.1
         version: 2.1.1
@@ -538,6 +541,19 @@ packages:
   '@tailwindcss/postcss@4.3.3':
     resolution: {integrity: sha512-JTSZZGQi1AyKirbLN3azmjVzef92tcX7h+iSqPdaeStyFpGpDlKvvpxeOE8njhbUanbRwr3z8DyzhICWnMtQeg==}
 
+  '@trpc/client@11.18.0':
+    resolution: {integrity: sha512-wOqeg3Fvl25V1ZisQhUD3K8G60ZJDlSGJNSyeXrLH24xAo5w6GSR2Kzb1cSNY9Y+IQ2YZvYGZstBU+V/ulo/ow==}
+    hasBin: true
+    peerDependencies:
+      '@trpc/server': 11.18.0
+      typescript: '>=5.7.2'
+
+  '@trpc/server@11.18.0':
+    resolution: {integrity: sha512-JAvXOuNTxgXjIDfQaOvDq1j66LMNfDJUH1IU7Slfn8EvRv2EkH6ehu3A7zpYhjO0syHHiYg77v2lG2JFJgvw7Q==}
+    hasBin: true
+    peerDependencies:
+      typescript: '>=5.7.2'
+
   '@tweenjs/tween.js@23.1.3':
     resolution: {integrity: sha512-vJmvvwFxYuGnF2axRtPYocag6Clbb5YS7kLL+SO/TeVFzHqDIWrNKYtcsPMibjDx9O+bu+psAy9NKfWklassUA==}
 
@@ -1376,6 +1392,15 @@ snapshots:
       postcss: 8.5.25
       tailwindcss: 4.3.3
 
+  '@trpc/client@11.18.0(@trpc/server@11.18.0(typescript@5.9.3))(typescript@5.9.3)':
+    dependencies:
+      '@trpc/server': 11.18.0(typescript@5.9.3)
+      typescript: 5.9.3
+
+  '@trpc/server@11.18.0(typescript@5.9.3)':
+    dependencies:
+      typescript: 5.9.3
+
   '@tweenjs/tween.js@23.1.3': {}
 
   '@types/node@20.19.43':