Backend (agent-engine.port.ts):
- Add `cancelled` event type: emitted when a task is cancelled (user-initiated
or injection), so Flutter can close the old stream cleanly
- Add `task_info` event type: emitted after inject to pass the new taskId to
the client, enabling cancel/re-inject on the replacement task
Flutter (features/chat/):
- ChatState: track current `taskId` alongside `sessionId`; clear on completion
or error
- Handle `TaskInfoEvent`: update taskId in state when server issues a new task
- Handle `CancelledEvent`: treat as stream termination (agentStatus → idle)
- MessageType.interrupted: new UI node (warning style) for mid-stream cancels
- _inject(): send text as an inject request while streaming; backend cancels
the current task and starts a new one with the injected message
- Input area: during streaming, hint changes to "追加指令...", Enter key calls
_inject() instead of _send(), and both inject-send + stop buttons are shown
- isAwaitingApproval kept separate from isStreaming so approval flow is not
blocked by inject mode
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Implement DB-based conversation message storage (engine-agnostic) that
works across both Claude API and Agent SDK engines. Add ChatGPT/Claude-style
conversation history drawer in Flutter with date-grouped session list,
session switching, and new chat functionality.
Backend: entity, repository, context service, migration 004, session/message
API endpoints. Flutter: ConversationDrawer, sessionId flow from backend
response via SessionInfoEvent, session list/switch/delete support.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
hailin