feat(task): refactor to Claude Code style individual tools

- Split unified Task tool into individual tools (TaskCreate, TaskGet, TaskList, TaskUpdate)
- Update schema to Claude Code field names (subject, blockedBy, blocks, activeForm, owner, metadata)
- Add OpenCode Todo API sync layer (todo-sync.ts)
- Implement Todo sync on task create/update for continuation enforcement
- Add comprehensive tests for all tools (96 tests total)
- Update AGENTS.md documentation

Breaking Changes:
- Field names changed: title→subject, dependsOn→blockedBy, open→pending
- Tool names changed: task→task_create, task_get, task_list, task_update

Closes: todo-continuation-enforcer now sees Task-created items

src/tools/index.ts

@@ -47,6 +47,12 @@ type OpencodeClient = PluginInput["client"]
 export { createCallOmoAgent } from "./call-omo-agent"
 export { createLookAt } from "./look-at"
 export { createDelegateTask } from "./delegate-task"
+export {
+  createTaskCreateTool,
+  createTaskGetTool,
+  createTaskList,
+  createTaskUpdateTool,
+} from "./task"
 
 export function createBackgroundTools(manager: BackgroundManager, client: OpencodeClient): Record<string, ToolDefinition> {
   const outputManager: BackgroundOutputManager = manager
@@ -73,5 +79,3 @@ export const builtinTools: Record<string, ToolDefinition> = {
   session_search,
   session_info,
 }
-
-export { createTask } from "./task"