feat(browser): add persistent Camofox sessions and VNC URL discovery (salvage #4400) (#4419)

Adds two Camofox features:

1. Persistent browser sessions: new `browser.camofox.managed_persistence`
   config option. When enabled, Hermes sends a deterministic profile-scoped
   userId to Camofox so the server maps it to a persistent browser profile
   directory. Cookies, logins, and browser state survive across restarts.
   Default remains ephemeral (random userId per session).

2. VNC URL discovery: Camofox /health endpoint returns vncPort when running
   in headed mode. Hermes constructs the VNC URL and includes it in navigate
   responses so the agent can share it with users.

Also fixes camofox_vision bug where call_llm response object was passed
directly to json.dumps instead of extracting .choices[0].message.content.

Changes from original PR:
- Removed browser_evaluate tool (separate feature, needs own PR)
- Removed snapshot truncation limit change (unrelated)
- Config.yaml only for managed_persistence (no env var, no version bump)
- Rewrote tests to use config mock instead of env var
- Reverted package-lock.json churn

Co-authored-by: analista <psikonetik@gmail.com.com>

hermes_cli/config.py

@@ -247,6 +247,13 @@ DEFAULT_CONFIG = {
         "command_timeout": 30,  # Timeout for browser commands in seconds (screenshot, navigate, etc.)
         "record_sessions": False,  # Auto-record browser sessions as WebM videos
         "allow_private_urls": False,  # Allow navigating to private/internal IPs (localhost, 192.168.x.x, etc.)
+        "camofox": {
+            # When true, Hermes sends a stable profile-scoped userId to Camofox
+            # so the server can map it to a persistent browser profile directory.
+            # Requires Camofox server to be configured with CAMOFOX_PROFILE_DIR.
+            # When false (default), each session gets a random userId (ephemeral).
+            "managed_persistence": False,
+        },
     },
 
     # Filesystem checkpoints — automatic snapshots before destructive file ops.
@@ -510,7 +517,7 @@ DEFAULT_CONFIG = {
     },
 
     # Config schema version - bump this when adding new required fields
-    "_config_version": 11,
+    "_config_version": 10,
 }
 
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