fix(browser): use 127.0.0.1 instead of localhost for CDP default (#10231)

/browser connect set BROWSER_CDP_URL to http://localhost:9222, but
Chrome's --remote-debugging-port only binds to 127.0.0.1 (IPv4).
On macOS, 'localhost' can resolve to ::1 (IPv6) first, causing both
_resolve_cdp_override's /json/version fetch and agent-browser's
--cdp connection to fail when Chrome isn't listening on IPv6.

The socket check in the connect handler already used 127.0.0.1
explicitly and succeeded, masking the mismatch.

Use 127.0.0.1 in the default CDP URL to match what Chrome actually
binds to.

cli.py

@@ -5956,7 +5956,7 @@ class HermesCLI:
         parts = cmd.strip().split(None, 1)
         sub = parts[1].lower().strip() if len(parts) > 1 else "status"
 
-        _DEFAULT_CDP = "http://localhost:9222"
+        _DEFAULT_CDP = "http://127.0.0.1:9222"
         current = os.environ.get("BROWSER_CDP_URL", "").strip()
 
         if sub.startswith("connect"):