feat: implement scheduler ratcheting by excluding completed tasks

- Update `torch-lock check` to scan `task-logs/<cadence>` for completed tasks.
- Add `--log-dir` and `--ignore-logs` flags to `check` command.
- Implement `getIsoWeekStr` utility for robust weekly cadence checking.
- Ensure completed agents are added to the `excluded` list, enabling the scheduler to skip them.
- Add comprehensive tests for log checking and date utilities.

Co-authored-by: PR0M3TH3AN <[email protected]>

test/utils.test.mjs

@@ -0,0 +1,36 @@
+import { describe, it } from 'node:test';
+import assert from 'node:assert';
+import { getIsoWeekStr } from '../src/utils.mjs';
+
+describe('Date Utilities', () => {
+  describe('getIsoWeekStr', () => {
+    it('returns correct ISO week for simple cases', () => {
+      assert.strictEqual(getIsoWeekStr('2023-01-02'), '2023-W01'); // Mon
+      assert.strictEqual(getIsoWeekStr('2023-01-08'), '2023-W01'); // Sun
+      assert.strictEqual(getIsoWeekStr('2023-01-09'), '2023-W02'); // Mon
+    });
+
+    it('handles year boundaries correctly', () => {
+      // 2023-01-01 is Sunday. Belong to last week of 2022.
+      assert.strictEqual(getIsoWeekStr('2023-01-01'), '2022-W52');
+      // 2024-01-01 is Monday. Week 1 of 2024.
+      assert.strictEqual(getIsoWeekStr('2024-01-01'), '2024-W01');
+      // 2023-12-31 is Sunday. Week 52 of 2023.
+      assert.strictEqual(getIsoWeekStr('2023-12-31'), '2023-W52');
+    });
+
+    it('handles leap years', () => {
+      assert.strictEqual(getIsoWeekStr('2024-02-29'), '2024-W09');
+    });
+
+    it('handles empty input (defaults to today)', () => {
+      // Just check it returns a string in correct format
+      const result = getIsoWeekStr();
+      assert.match(result, /^\d{4}-W\d{2}$/);
+    });
+
+    it('handles invalid input gracefully', () => {
+      assert.strictEqual(getIsoWeekStr('invalid-date'), '');
+    });
+  });
+});