fix(test): single shared workspace, remove per-worker subdirs (keep lock mechanism)

tests/conftest.py

@@ -482,10 +482,9 @@ def live_gui(request) -> Generator["_LiveGuiHandle", None, None]:
  diag = VerificationLogger("live_gui_startup", "live_gui_diag")
  diag.log_state("GUI Script", "N/A", "gui_2.py")
  
- # 1. Create a per-worker subdirectory under the run workspace so xdist workers
- #    don't pollute the main directory or collide on port 8999.
- _worker_id = os.environ.get("PYTEST_XDIST_WORKER", "master")
- temp_workspace = _RUN_WORKSPACE / _worker_id
+ # 1. Create the run workspace (one per pytest invocation, shared by the
+ #    single owner worker that actually runs live_gui tests).
+ temp_workspace = _RUN_WORKSPACE
  if temp_workspace.exists():
   for _ in range(5):
    try:
@@ -558,6 +557,7 @@ def live_gui(request) -> Generator["_LiveGuiHandle", None, None]:
  # the lock and wait for the hook server to come up, then yield a client
  # handle (process=None; teardown skips kill + workspace cleanup). This
  # serializes I/O on port 8999 so we don't try to run live_gui in parallel.
+ _worker_id = os.environ.get("PYTEST_XDIST_WORKER", "master")
  _owner_lock = temp_workspace / ".live_gui_owner.lock"
  _is_owner = False
  try: