fix(bot-screen): vault page operations honour the human lease

browser_vault_fill / enter_code / save_login reach the page over the supervisor CDP socket, outside
_run_browser_command, so they skipped the Bot Desktop fence: with a human holding the screen an ordinary
browser_snapshot was refused while enter_code focused, inspected and wrote to the very form the human was
typing into. Their tool handlers now run under the same run_fenced admission + epoch check as every other
page access.

tests/tools/test_bot_desktop_browser_fence.py

@@ -109,3 +109,23 @@ def test_browser_console_supervisor_fast_path_is_fenced_while_human_controls_sha
     assert evaluated == [] and commands == [], "human holds the lease, yet the page was evaluated"
     assert "WHAT-THE-HUMAN-TYPED" not in raw
     assert result.get("code") == "human_has_control"
+
+
+def test_vault_page_operations_respect_the_human_lease(monkeypatch):
+    """The vault tools reach the page over the supervisor socket, outside `_run_browser_command`: while a
+    human holds the screen they must be refused like every other page access, and never focus, inspect or
+    write to the form the human is typing into."""
+    from tools import browser_tool as browser
+    from tools import browser_vault_tool as vault
+
+    browser._active_sessions["default"] = {"session_name": "review", "cdp_url": None, "features": {"local": True}}
+    touched = []
+    for name in ("browser_vault_fill", "browser_vault_enter_code", "browser_vault_save_login"):
+        monkeypatch.setattr(vault, name, lambda *a, **k: touched.append(name) or json.dumps({"success": True}))
+    lease.acquire("human")
+    for handler in (vault._handle_vault_fill, vault._handle_vault_enter_code, vault._handle_vault_save_login):
+        res = json.loads(handler({"handle": "vault_x"}, task_id="default"))
+        assert res["code"] == "human_has_control", handler.__name__
+    assert touched == [], "no vault page access while the human holds the screen"
+    lease.release("human")
+    assert json.loads(vault._handle_vault_fill({"handle": "vault_x"}, task_id="default"))["success"] is True

tools/browser_vault_tool.py

@@ -660,12 +660,26 @@ BROWSER_VAULT_ENTER_CODE_SCHEMA = {
 }
 
 
+def _fenced_page_op(task_id: Optional[str], fn) -> str:
+    """Vault operations focus, inspect and fill the page over the supervisor socket, bypassing
+    ``_run_browser_command``; they must honour the Bot Desktop lease like every other page access,
+    or a human typing a credential on the taken-over screen could be read or written to."""
+    from tools.browser_tool import _active_sessions, _last_session_key
+    from tools.browser_tool_session import run_fenced
+
+    session = _active_sessions.get(_last_session_key(task_id or "default")) or {}
+    res = run_fenced(session, lambda: {"raw": fn()})
+    return res["raw"] if "raw" in res else json.dumps(res)
+
+
 def _handle_vault_enter_code(args: Dict[str, Any], **kwargs) -> str:
-    return browser_vault_enter_code(handle=str(args.get("handle") or ""), task_id=kwargs.get("task_id"))
+    tid = kwargs.get("task_id")
+    return _fenced_page_op(tid, lambda: browser_vault_enter_code(handle=str(args.get("handle") or ""), task_id=tid))
 
 
 def _handle_vault_save_login(args: Dict[str, Any], **kwargs) -> str:
-    return browser_vault_save_login(label=str(args.get("label") or ""), task_id=kwargs.get("task_id"))
+    tid = kwargs.get("task_id")
+    return _fenced_page_op(tid, lambda: browser_vault_save_login(label=str(args.get("label") or ""), task_id=tid))
 
 
 def _handle_vault_list(args: Dict[str, Any], **kwargs) -> str:
@@ -677,9 +691,8 @@ def _handle_vault_unlock(args: Dict[str, Any], **kwargs) -> str:
 
 
 def _handle_vault_fill(args: Dict[str, Any], **kwargs) -> str:
-    return browser_vault_fill(
-        handle=str(args.get("handle") or ""), task_id=kwargs.get("task_id")
-    )
+    tid = kwargs.get("task_id")
+    return _fenced_page_op(tid, lambda: browser_vault_fill(handle=str(args.get("handle") or ""), task_id=tid))
 
 
 from tools.registry import no_cache_check_fn, registry  # noqa: E402