fix(docker+brain): make container Chrome search work, harden, improve toggle

Addresses review findings on the dockerized stack:
- Container Chrome search was dead: add --remote-debugging-port + a non-default
  --user-data-dir (Chrome 136+ refuses CDP on the default profile), add the
  playwright dep (browse-search.mjs connectOverCDP) with browser download
  skipped, and connect to 127.0.0.1 not "localhost" (container localhost -> ::1
  while Chrome binds IPv4). Verified: browse-search returns real results.
- Broadcast toggle reliability: always offer setBroadcast in screen-share mode
  (the embedding/keyword router dropped it for non-English utterances) and make
  its description force a tool call. "방송 꺼줘"->stop now 5/5; no false triggers.
- Stop the broadcast on voice leave (no orphaned stream).
- Security: bind VNC/noVNC to loopback by default (VNC_BIND override) and the
  bridge to the container loopback (BRIDGE_HOST=127.0.0.1), not published.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docker-compose.yml

@@ -68,14 +68,17 @@ services:
       - "nvidia.com/gpu=all"
     shm_size: "1gb"          # Chrome needs a larger /dev/shm
     ports:
-      # Host ports are overridable. If the HOST already runs VNC on 5901
-      # (see docs/vnc-xfce-setup.md), set VNC_PORT=5902 in .env — this server
-      # does, so .env pins VNC_PORT=5902.
-      - "${VNC_PORT:-5901}:5901"      # VNC
-      - "${NOVNC_PORT:-6080}:6080"    # noVNC (open in a browser)
-      # Brain bridge: bind to loopback only — it is an internal bot<->brain API
-      # with no auth and must not be reachable off-host.
-      - "127.0.0.1:${BRIDGE_PORT:-8765}:8765"
+      # All published to loopback only by default — VNC/noVNC use a weak default
+      # password and the bridge is an unauthenticated internal API, so none
+      # should be reachable off-host. For remote access use an SSH tunnel, or
+      # set a strong VNC_PASSWORD and override the bind (e.g. VNC_BIND=0.0.0.0).
+      # Host VNC port is overridable; this server already runs Xvnc on 5901 so
+      # .env pins VNC_PORT=5902.
+      - "${VNC_BIND:-127.0.0.1}:${VNC_PORT:-5901}:5901"      # VNC
+      - "${VNC_BIND:-127.0.0.1}:${NOVNC_PORT:-6080}:6080"    # noVNC (browser)
+      # The brain bridge is NOT published: it binds the container's loopback
+      # (BRIDGE_HOST=127.0.0.1) and is only consumed by the bot in this same
+      # container, so it needs no host port and stays unreachable off-container.
     volumes:
       - javis_data:/data                         # jarvis db + memory
       - whisper_cache:/root/.cache/huggingface   # cached Whisper models