feat: v2.2.0 — faster fallback with first-byte timeout

- Reduced default CLAUDE_TIMEOUT from 300s to 120s for faster fallback
- Added CLAUDE_FIRST_BYTE_TIMEOUT (default 30s): aborts early if Claude
  CLI produces no output, preventing silent hangs
- First-byte timing logged for every request for observability
- Health endpoint now reports firstByteTimeout in config

package.json

@@ -1,6 +1,6 @@
 {
   "name": "openclaw-claude-proxy",
-  "version": "2.0.0",
+  "version": "2.2.0",
   "description": "OpenAI-compatible proxy that routes requests through Claude CLI \u2014 use your Claude Pro/Max subscription as an OpenClaw model provider",
   "type": "module",
   "bin": {