chore(release): v0.5.0

Manual version bump to 0.5.0 (changeset version produced 1.0.0 from a
single minor changeset against 0.4.1; that release was rolled back and
the 1.0.0 npm version deprecated).

Aggregates: status terminology refresh (planning/replan), Reviewer
rename, in-review pause behavior, dashboard-tui resize hardening,
dev-server experimental toggle fix, version reporting fix.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/engine/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@fusion/engine",
-  "version": "0.4.1",
+  "version": "0.5.0",
   "license": "MIT",
   "description": "Fusion engine: executor, merger, scheduler, and automation runtime for the Fusion AI coding agent.",
   "homepage": "https://github.com/Runfusion/Fusion#readme",