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/lib/newBuildReload.ts

@@ -0,0 +1,46 @@
+/**
+ * @file newBuildReload.ts
+ * @description Reloads the tab onto the new UI build after the server was
+ * updated. Every update — the dashboard's own Update button in any tab,
+ * `/agenthub-update`, a restart onto a newer plugin — drops the WebSocket; when
+ * it comes back, `GET /api/health` names the server's version, and a version
+ * other than this bundle's `__APP_VERSION__` means the page is stale. At most
+ * one reload per version (sessionStorage), so a server whose UI build failed
+ * cannot make the tab reload on every reconnect.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+import { eventBus } from "./eventBus";
+
+const KEY = "agenthub.reloadedFor";
+
+export function reloadOnNewBuild({
+  bundle = __APP_VERSION__,
+  health = () => fetch("/api/health").then((r) => r.json() as Promise<{ version?: string }>),
+  reload = () => window.location.reload(),
+  storage = window.sessionStorage,
+}: {
+  bundle?: string;
+  health?: () => Promise<{ version?: string }>;
+  reload?: () => void;
+  storage?: Pick<Storage, "getItem" | "setItem">;
+} = {}): () => void {
+  let wasDown = false;
+  return eventBus.onConnection((up) => {
+    if (!up) {
+      wasDown = true;
+      return;
+    }
+    if (!wasDown) return;
+    wasDown = false;
+    health()
+      .then(({ version }) => {
+        if (!version || version === bundle || storage.getItem(KEY) === version) return;
+        storage.setItem(KEY, version);
+        reload();
+      })
+      .catch(() => {
+        /* the next reconnect asks again */
+      });
+  });
+}