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

server/lib/git-diff.js

@@ -77,8 +77,8 @@ const VALID_RANGES = new Set(["work", "branch", "commit"]);
  *  pathspec. `git` is called with an argv array, so this is belt-and-braces. */
 const SAFE_REV = /^[A-Za-z0-9][A-Za-z0-9._\/-]{0,200}$/;
 /** The file whose CONTENT this module never returns, at any rev and at ANY
- *  depth: `settings.local.json` is where router-apply.js writes a lane's AI
- *  Router API key, and key material never leaves the server. Any depth,
+ *  depth: `settings.local.json` is where AgentHub once wrote a lane's AI
+ *  Proxy API key, and key material never leaves the server. Any depth,
  *  because a lane at the repo root sees a subdirectory lane's key as
  *  `sub/.claude/settings.local.json`. Lower-cased: a case-insensitive
  *  filesystem (macOS) opens it under any casing. */