feat: make attempt_completion tool conditional based on task context

- Add isOrchestrated flag to Task class to track subtask context
- Always include attempt_completion for orchestrated subtasks
- Make attempt_completion optional for standard tasks via allowAttemptCompletion setting
- Default behavior excludes attempt_completion for standard tasks
- Add comprehensive tests for conditional inclusion logic
- Update UI components to expose the new setting
- Update snapshots to reflect new default behavior

Fixes #7529

Author: roomote

packages/types/src/global-settings.ts

@@ -62,6 +62,7 @@ export const globalSettingsSchema = z.object({
 	alwaysAllowFollowupQuestions: z.boolean().optional(),
 	followupAutoApproveTimeoutMs: z.number().optional(),
 	alwaysAllowUpdateTodoList: z.boolean().optional(),
+	allowAttemptCompletion: z.boolean().optional(),
 	allowedCommands: z.array(z.string()).optional(),
 	deniedCommands: z.array(z.string()).optional(),
 	commandExecutionTimeout: z.number().optional(),