- dialogue_box.gd: panel is always visible as permanent insert UI
element per D-061 — content fades but frame stays on screen
- protocol.gd: bump PROTOCOL_VERSION to 13
- Makefile: add check-protocol target that verifies server/client
protocol versions match, runs automatically before build
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>