Gengchou v2.3.0

Gengchou v2.3.0

v2.3.0 completes the internal identity transition begun on the 2.2.x line.
It is intentionally limited to removing the one-time bridge and publishing a
single, unambiguous Gengchou package surface.

Changes

• Remove the completed settings, cache, startup-entry, and runtime-identity
  migration state machine.
• Use only the Gengchou mutex, window classes, data directories, relaunch
  variables, and updater readiness protocol.
• Publish only gengchou.exe and gengchou-windows-x64.zip; compatibility
  asset aliases and the bridge verifier are no longer part of new releases.
• Add a CI and release gate that rejects retired identity strings outside the
  acknowledgements, provenance record, and historical release notes.

Updating

Users who completed the v2.2.4 bridge can replace the existing executable with
gengchou.exe and start it normally. Settings, cache, startup preference, and
window positions remain under the Gengchou data directories.

Do not update an installation older than v2.2.4 directly to this release. The
v2.2.4 release remains available as the required bridge.