1. Remove duplicate ToolResult definition in heartbeat package
- Import tools.ToolResult instead of local definition
- Add nil check for handler before execution
2. Fix SpawnTool to return AsyncResult and implement AsyncTool
- Add callback field and SetCallback method
- Return AsyncResult instead of NewToolResult
3. Add context cancellation support to SubagentManager
- Check ctx.Done() before and during task execution
- Set task status to "cancelled" on cancellation
- Call callback with result on completion
4. Fix data race window in CronTool.addJob
- Use Lock instead of RLock for channel/chatID access
- Ensure consistent snapshot during job creation
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Update all Tool implementations to return *ToolResult instead of (string, error)
- ShellTool: returns UserResult for command output, ErrorResult for failures
- SpawnTool: returns NewToolResult on success, ErrorResult on failure
- WebTool: returns ToolResult with ForUser=content, ForLLM=summary
- EditTool: returns SilentResult for silent edits, ErrorResult on failure
- FilesystemTool: returns SilentResult/NewToolResult for operations, ErrorResult on failure
- Temporarily disable cronTool in main.go (will be re-enabled in US-016)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
