style: ruff format after MCP server integration

Reformat the files touched by Tasks 1-14 of the host-agent MCP server
plan. No semantic changes; pre-existing format issues in unrelated
files (test_templates, test_skill_sync_wiring, 0010_skill_management,
test_skill_catalog_mcp) left untouched for a separate housekeeping
pass.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/device-host-agent/host_agent/assignment.py

@@ -51,8 +51,7 @@ class AssignmentExecutor:
             return AssignmentExecutionResult(
                 status="failed",
                 failure_reason=(
-                    f"device {assignment.device_id} is held by an active "
-                    "MCP session"
+                    f"device {assignment.device_id} is held by an active MCP session"
                 ),
             )
         with bind_planner_execution_context(assignment):

apps/device-host-agent/host_agent/mcp_lock.py

@@ -57,9 +57,7 @@ class McpBusyTracker:
             lease = McpDeviceLease(
                 device_id=device_id,
                 session_id=session_id,
-                acquired_at=(
-                    existing.acquired_at if existing is not None else now
-                ),
+                acquired_at=(existing.acquired_at if existing is not None else now),
                 last_seen_at=now,
             )
             self._leases[device_id] = lease
@@ -154,4 +152,4 @@ class McpBusyTracker:
             if (cutoff - lease.last_seen_at).total_seconds() > self._ttl
         ]
         for device_id in expired:
-            del self._leases[device_id]
+            del self._leases[device_id]

apps/device-host-agent/host_agent/mcp_token.py

@@ -74,9 +74,7 @@ class McpTokenStore:
                 created_at=datetime.fromisoformat(str(data["created_at"])),
             )
         except (KeyError, TypeError, ValueError) as exc:
-            raise McpTokenStoreError(
-                f"MCP token file schema invalid: {exc}"
-            ) from exc
+            raise McpTokenStoreError(f"MCP token file schema invalid: {exc}") from exc
 
     def _generate_and_write(self) -> McpToken:
         token = McpToken(

apps/device-host-agent/host_agent/web/mcp.py

@@ -141,9 +141,7 @@ def _wrap_tool(
             return _with_display_status(handler, status_tracker, *args, **kwargs)
 
         if device_id is not None and tool_name not in _NON_DEVICE_TOOLS:
-            _check_and_acquire(
-                device_id, session_id, mcp_busy_tracker, status_tracker
-            )
+            _check_and_acquire(device_id, session_id, mcp_busy_tracker, status_tracker)
 
         return handler(*args, **kwargs)
 
@@ -254,4 +252,4 @@ def _call_tool_sync(
             raise KeyError(f"tool {tool_name!r} has no callable")
         return fn(**arguments)
     finally:
-        _TEST_SESSION_ID.reset(token)
+        _TEST_SESSION_ID.reset(token)