fix(background-task): clarify task id contracts

src/features/builtin-commands/templates/init-deep.ts

@@ -135,7 +135,7 @@ LspFindReferences(filePath="...", line=X, character=Y)
 
 \`\`\`
 // After main session analysis done, collect all task results
-for each task_id: background_output(task_id="...")
+for each background task ID (\`bg_...\`): background_output(task_id="bg_...")
 \`\`\`
 
 **Merge: bash + LSP + existing + explore findings. Mark "discovery" as completed.**

src/features/builtin-skills/skills/review-work.ts

@@ -481,7 +481,7 @@ OUTPUT FORMAT:
 
 After launching all 5 agents in one turn, **end your response**. Wait for system notifications as each agent completes.
 
-As each completes, collect via \`background_output(task_id="...")\`. Store each verdict:
+As each completes, collect via \`background_output(task_id="bg_...")\`. Store each verdict:
 
 | Agent | Verdict | Notes |
 |-------|---------|-------|