fix(cron): match restricted day fields with OR

[blueberrycongee]

Summary

Fix the Cron day-of-month/day-of-week matching rule. When both fields are restricted, Unix cron runs when either matches; PilotDeck previously required both.

For 0 9 1 * 1, starting at 2026-06-02T00:00:00Z:

• Before: 2027-02-01T09:00:00Z (the next Monday that is also the first).
• After: 2026-06-08T09:00:00Z (the next Monday).

Changes

• Preserve the original day-field syntax and use OR only when neither field starts with *. Keep AND for wildcard fields, including */n, following Cronie's matching rule.
• Keep month/hour/minute constraints and timezone handling. Do not mistake explicit full ranges such as 0-6 for wildcards.
• Restrict the leap-day fast path to genuinely leap-day-only schedules; 29 2 0-6 must also run on other February dates under OR semantics.
• Advance the schedule computation version to 3 so startup repairs cached future execution dates. Preserve already-due version-2 runs for catch-up, leave one-time schedules alone, and avoid recalculating migrated tasks on subsequent restarts.
• Add 16 matcher cases plus a persisted-task migration/restart regression test. No UI or dependency changes.

Validation

Using Node 22.23.3:

• npm run build — passed.
• node --import tsx --test tests/cron/cron-schedule.test.ts tests/cron/cron-editing.spec.ts — 27 passed.
• Before the fix, 10 of the 16 matcher cases failed. The migration regression also failed independently before the cache-version change.
• Full compiled suite: 642 passed, 0 failed, 9 cancelled, 2 skipped (653 total; nonzero exit due to cancellations).
• Repeated the same full build and suite in a separate clean worktree at upstream f0ca40f4: 625 passed, 0 failed, the same 9 cancelled, 2 skipped (636 total). All 17 added tests pass.

The pre-existing cancellations are seven cases in tests/network/fetch.spec.ts and two in tests/task/background-task-runtime.spec.ts, all reporting Promise resolution is still pending but the event loop has already resolved. They are outside this PR's scope.