42ba961075
Store the user's unsent message editor text in DbThread so it survives quitting and reloading Zed. The draft flows through Thread → AcpThread → AcpThreadView on load, and back via a debounced observer on the message editor for saves. Currently works for native Zed agents only; external ACP agents will pick this up once general ACP history persistence lands. ## Changes - **`DbThread`** / **`Thread`**: New `draft_prompt: Option<String>` field, included in `to_db()`/`from_db()` - **`AcpThread`**: Bridge field with getter/setter, populated during `register_session()` - **`NativeAgent::save_thread()`**: Copies draft from `AcpThread` → `Thread` before persisting - **`AcpThreadView`**: Restores draft into `MessageEditor` on load; syncs editor text → `AcpThread` via observer; debounced (500ms) Thread notify triggers DB save Co-authored-by: Anthony Eid <anthony@zed.dev> Co-authored-by: Mikayla Maki <mikayla@zed.dev>