Polish tool-window methods: error format, logging, async test

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/hqt/sessions/service.py

@@ -410,6 +410,7 @@ class SessionService:
         for an unknown tool, a missing binary, or a missing session/project.
         Returns the new window_id, or None if the tmux spawn fails.
         """
+        log.info("Opening tool window: session=%s tool=%s", session_id, tool)
         spec = TOOLS.get(tool)
         if spec is None:
             raise ServiceError(f"Unknown tool '{tool}'")
@@ -421,7 +422,7 @@ class SessionService:
                 raise ServiceError("Session not found")
             project = db.get(Project, sess.project_id)
             if project is None:
-                raise ServiceError("Project no longer exists")
+                raise ServiceError(f"Project {sess.project_id} no longer exists")
             cwd = project.path
             label = f"{spec.label} · {project.name}"
         return await self.tmux.open_aux_window(spec.label, cwd, spec.command, label)

tests/test_sessions.py

@@ -1574,10 +1574,9 @@ async def test_open_tool_window_unknown_session_raises(service, monkeypatch):
         await service.open_tool_window(999, "nvim")
 
 
-def test_session_id_for_window_resolves_and_misses(service, db):
-    import asyncio
-
-    asyncio.run(service.create_session(project_id=1, harness_name="claude-code"))
+@pytest.mark.asyncio
+async def test_session_id_for_window_resolves_and_misses(service, db):
+    await service.create_session(project_id=1, harness_name="claude-code")
     assert service.session_id_for_window("hqt-1") == 1
     assert service.session_id_for_window("not-an-hqt-window") is None