Expand the 0.9.5 release-candidate checklist

Replace the remaining-gap table with v0.9.0 baselines and break the release
candidate into detailed workstreams for content lock/playtests, balance,
save migration, release engineering, legal/credits, documentation/visual
sign-off and final QA. Sync the README development status to v0.9.0.

README.md

@@ -118,11 +118,12 @@ Full setup, every run/test/smoke command, and the controls table are in
 
 ## Development Status
 
-v0.8.0 adds the first-shift tutorial, campaign shell, checkpoint resume,
-difficulty presets and an in-game Help overlay on top of the v0.7.x venue, gear,
-judge and Desktop HQ work. See [`docs/development-status.md`](docs/development-status.md)
-for the implemented list and [`TODO.md`](TODO.md) for the v1.0.0 roadmap. Manual
-verification uses the [`docs/smoke-checklist.md`](docs/smoke-checklist.md).
+v0.9.0 adds the production-quality baseline: mixer/accessibility settings, a
+24-NPC performance budget and the documented Godot 4.3-CI/4.7-local matrix, on
+top of v0.8's tutorial, campaign, checkpoint resume, difficulty and Help. See
+[`docs/development-status.md`](docs/development-status.md) for the implemented
+list and [`TODO.md`](TODO.md) for the v1.0.0 roadmap. Manual verification uses
+the [`docs/smoke-checklist.md`](docs/smoke-checklist.md).
 
 ## Development Workflow