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>

website/docs/reference/environment-variables.md

@@ -85,6 +85,7 @@ For native Anthropic auth, Hermes prefers Claude Code's own credential files whe
 | `BROWSERBASE_PROJECT_ID` | Browserbase project ID |
 | `BROWSER_USE_API_KEY` | Browser Use cloud browser API key ([browser-use.com](https://browser-use.com/)) |
 | `BROWSER_CDP_URL` | Chrome DevTools Protocol URL for local browser (set via `/browser connect`, e.g. `ws://localhost:9222`) |
+| `CAMOFOX_URL` | Camofox local anti-detection browser URL (default: `http://localhost:9377`) |
 | `BROWSER_INACTIVITY_TIMEOUT` | Browser session inactivity timeout in seconds |
 | `FAL_KEY` | Image generation ([fal.ai](https://fal.ai/)) |
 | `GROQ_API_KEY` | Groq Whisper STT API key ([groq.com](https://groq.com/)) |