Add idempotency guard to completeTask — prevent double API calls

[xliry]

Problem

From agent logs, lota-1 called POST /tasks/148/complete twice (consecutive calls). This wastes API calls and could cause race conditions (double close, double label swap).

What to do

In src/github.ts, completeTask() function:

1. At the start of the function, check if the task already has status:completed label
2. If already completed, return early with a success response (idempotent)
3. Don't post a duplicate completion comment or try to re-close

async function completeTask(id: number, body: any) {
  // Idempotency check
  const issue = await gh(`/repos/${REPO}/issues/${id}`);
  const labels = issue.labels.map((l: any) => l.name);
  if (labels.includes('status:completed')) {
    return { ok: true, message: 'Already completed (idempotent)' };
  }
  // ... rest of completion logic
}

Acceptance

• Double-calling /complete is harmless (idempotent)
• No duplicate comments or label swaps
• Build passes: npm run build

[xliry]

Plan

• Fetch the issue at the start of completeTask() to read current labels
• If status:completed label is already present, return early with { ok: true, message: 'Already completed (idempotent)' }
• Skip posting duplicate comment, label swap, and issue close
• Run npm run build to verify no regressions
• Commit and push

[xliry]

Completion Report

Added idempotency guard to completeTask() in src/github.ts. At the start of the function, the issue is fetched and its labels checked. If status:completed is already present, the function returns { ok: true, message: 'Already completed (idempotent)' } immediately — skipping the comment post, label swap, and issue close. Build passes cleanly.

Modified: src/github.ts