feat: v2.5.5 — AI Router renamed AI Proxy, reload onto new builds, update no longer spins

AI Proxy (was AI Router):
- server/lib/ai-proxies.js, proxy-apply.js, routes/ai-proxies.js mounted at
  /api/ai-proxies and the old /api/ai-routers; `router` still accepted on the
  start routes; profiles move to <CLAUDE_HOME>/agenthub-proxies/
- dashboard_runs.router renamed in place to proxy: an older build on the same
  DB fails on that column, so dev and prod sharing one DB update together
- a proxy's baseUrl stored as its root (a typed /v1 made /v1/v1/messages);
  Test probes Claude /v1/messages and Codex /v1/responses
- Settings → AI Proxy (/settings/ai-router redirects), ProxyPicker

Updates:
- every tab reloads onto the new UI build when its WebSocket reconnects to a
  server of another version (lib/newBuildReload.ts, once per version)
- Update now stops waiting on a plugin chain that failed or pulled nothing
  (the old server never goes down), and reloads as soon as a new version answers

Also:
- a pane whose command exits at once says so (EPANEEXITED) instead of
  "Command failed: tmux set-option … mouse on"
- the pane drag preview draws where the pane actually lands

client/src/components/lanes/__tests__/LaneCard.test.tsx

@@ -28,7 +28,7 @@ vi.mock("../../../lib/api", () => ({
     locks: {
       list: vi.fn(),
     },
-    aiRouters: {
+    aiProxies: {
       list: vi.fn(),
     },
     run: {
@@ -45,10 +45,10 @@ beforeEach(() => {
   // stack, so the runtime strip and its button stay absent unless a test opts in.
   vi.mocked(api.lanes.runtime).mockReset();
   vi.mocked(api.lanes.runtime).mockResolvedValue({ available: false });
-  // Only the built-in profile by default: a user who never opened the AI Router
+  // Only the built-in profile by default: a user who never opened the AI Proxy
   // tab has nothing to switch between, so the row stays out of every other test.
-  vi.mocked(api.aiRouters.list).mockReset();
-  vi.mocked(api.aiRouters.list).mockResolvedValue({ items: [] });
+  vi.mocked(api.aiProxies.list).mockReset();
+  vi.mocked(api.aiProxies.list).mockResolvedValue({ items: [] });
 });
 vi.mocked(api.locks.list).mockReset();
 vi.mocked(api.locks.list).mockResolvedValue({ locks: [] });