feat/cq-calendar-month-intervals

[DaZuiZui]

What is changed

Implement calendar-aware mo/y durations for Continuous Query EVERY and RANGE clauses, based on the agreed design in #18428.

• Preserve structured (monthPart, fixedPart) durations through parsing and the CQ request.
• Calculate occurrences and RANGE endpoints from the original boundary in the persisted zone, including month-end, leap-year, and DST behavior.
• Add versioned structured duration fields to TCreateCQReq, with validation and legacy sentinel handling.
• Version CQ snapshots while retaining legacy fixed-duration snapshot compatibility.
• Use actual occurrence distance for execution timeout and avoid advancing stale callbacks.
• Add checked duration parsing/arithmetic and component-wise semantic validation.

Verification

git diff --check passes. Full Maven compilation is currently blocked by pre-existing generated Thrift/API version mismatches in this checkout.

Fixes #18428