docs(changelog): cut 0.49.0 — sync transparency, local backup, full-cluster ambiguity gate

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -6,6 +6,29 @@ project follows [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+## [0.49.0] — 2026-07-16
+
+### Added
+
+- **See what sync did.** After every sync, the Account tab shows exactly
+  what the merge decided — a "no conflicts" note, or one line per
+  reconciled field with both values ("this device: 3 / server: 5"). When
+  a merge wasn't clean, a toast summarises it: "Synced — 2 conflicts,
+  kept newer values". (#189)
+- **One-file backup.** Settings → Account → Local data can now export
+  every save (settings, stats, achievements, progress) into a single
+  backup file next to your other saves — and restore from it later or on
+  another machine. Restores never silently reset anything: a missing or
+  incompatible backup shows an error and leaves your data untouched.
+  (#189)
+
+### Changed
+
+- Under the hood, the scheduler-ambiguity gate now covers the full
+  plugin cluster (22 plugins) — 585 undefined-order system pairs were
+  pinned or proven independent, eliminating a whole class of
+  "works-on-my-frame" bugs in modes, replays, input, and chrome. (#188)
+
 ## [0.48.1] — 2026-07-15
 
 ### Added