v0.2.3

Picks up sigil-caldav v0.10.1's TZID-aware recurrence walker so TZID-tagged recurring events keep their wall-clock anchor across DST transitions. Fixes the CodeSignal Simulation/Team-coffee miscount where winter-serialized 17:00 EET events rendered as 16:00 EEST during summer.

No bureau-side code changes — pure dep refresh + regression test.