release: renumber crash-report release to v2.7.2

v2.7.1 is taken by the launch-crash fix (calendar observer registered before
the permission gate). Bump this held crash-reporting release to 2.7.2.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -7,7 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [2.7.1] — 2026-06-18
+## [2.7.2] — 2026-06-18
 
 ### Added
 - Crash reporting you control. If Calendula closes unexpectedly, it now captures