feat(council-archive): register council tools and add write_output_to_file to task tool

- Register council_finalize and council_read in tool registry
- Add write_output_to_file param to delegate-task, propagate to LaunchInput
- Create council-archive barrel exports

src/tools/index.ts

@@ -47,6 +47,7 @@ export {
 } from "./task"
 export { createHashlineEditTool } from "./hashline-edit"
 export { createPrepareCouncilPromptTool } from "./prepare-council-prompt"
+export { createCouncilFinalize, createCouncilRead } from "./council-archive"
 
 export function createBackgroundTools(manager: BackgroundManager, client: OpencodeClient): Record<string, ToolDefinition> {
   const outputManager: BackgroundOutputManager = manager