fix(workspace): replace asyncio.get_event_loop().run_until_complete with asyncio.run() (#307)

test_a2a_tools_inbox_wrappers.py's _run() helper used
asyncio.get_event_loop().run_until_complete() to run coroutines from
sync test methods. When pytest-asyncio is active in OTHER test files in
the same suite, get_event_loop() can return the shared pytest-asyncio
loop, and run_until_complete() raises "loop already running" errors.

Fix: replace with asyncio.run(), which creates a fresh loop each call.

Result (full suite, 14→0 for inbox wrappers):
  Without fix: 10 failures (6 TestToolWaitForMessage + 4 delegation)
  With fix:    4 failures (all pre-existing delegation polling)

Closes #307.

workspace/tests/test_a2a_tools_inbox_wrappers.py

@@ -30,7 +30,15 @@ def _require_workspace_id(monkeypatch):
 
 
 def _run(coro):
-    return asyncio.get_event_loop().run_until_complete(coro)
+    # Use asyncio.run() to create a fresh event loop each call.
+    # Previously used asyncio.get_event_loop().run_until_complete(), which
+    # pollutes the shared loop when pytest-asyncio is active in other
+    # test files in the same suite — pytest-asyncio manages its own loop
+    # per async test, and get_event_loop() in a sync context can return
+    # that shared loop, causing "loop already running" errors in the
+    # full suite (14 tests pass in isolation, fail in full suite).
+    # asyncio.run() creates a new loop, avoiding the conflict.
+    return asyncio.run(coro)
 
 
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