d14734df1f
main folded the plugin's contextvars-inheriting thread wrapper into agent.memory_provider.spawn_context_thread. The registry this stack adds for join_plugin_threads keeps a thin client.spawn_context_thread that calls the core spawner and records the thread under its owner; the four spawn sites import it from client. main's inherit-profile test builds a real provider now that _spawn_write is an instance method (the owner is what gets joined).