fix: propagate caller contextvars into the Feishu adapter-owned executor

Moving the dedup flush and thread lookup from asyncio.to_thread onto the
adapter-owned pool fixed the torn-down default executor, but to_thread also
copies the caller's contextvars and run_in_executor does not. A multiplexed
profile's HERMES_HOME override and secret scope are contextvars, so those
workers silently ran under the launch profile. _run_blocking now runs the call
through contextvars.copy_context().run, matching to_thread semantics.

Review finding: _run_blocking lost the profile HERMES_HOME override / secret scope on the worker.

plugins/platforms/feishu/adapter.py

@@ -1383,9 +1383,14 @@ class FeishuAdapter(BasePlatformAdapter):
             return executor
 
     async def _run_blocking(self, func, *args):
-        """Run a blocking Feishu SDK call on the adapter-owned thread pool."""
+        """Run a blocking Feishu SDK call on the adapter-owned thread pool.
+
+        ``copy_context().run`` mirrors ``asyncio.to_thread``: the worker sees the caller's
+        profile HERMES_HOME override / secret scope (multiplexed dedup flush, thread lookup).
+        """
         loop = asyncio.get_running_loop()
-        return await loop.run_in_executor(self._get_sdk_executor(), func, *args)
+        return await loop.run_in_executor(
+            self._get_sdk_executor(), contextvars.copy_context().run, func, *args)
 
     def _shutdown_sdk_executor(self) -> None:
         """Stop the adapter-owned SDK executor without touching the loop default."""