Force safe WebKit render profile for Gravity Omega

[VrtxOmega]

Summary

• Default the native Gravity Omega launcher to an explicit x11-safe render profile on COSMIC/Wayland.
• Export GDK_BACKEND=x11 when DISPLAY is available, plus software-safe WebKit/GTK rendering flags.
• Log the effective render profile/backend/display state for future crash evidence.
• Scope the stale-binary freshness guard to actual app-binary inputs so launcher-only commits do not falsely block launch.
• Extend scaffold validation for the new render-profile contract.

Evidence

• Reproduced fresh-build close: PID 2747935 exited within about 32 seconds and launcher captured Gdk-Message: 09:55:28.314: Lost connection to Wayland compositor.
• Active session environment was WAYLAND_DISPLAY=wayland-1, DISPLAY=:1, XDG_SESSION_TYPE=wayland, GDK_BACKEND=wayland.
• Dry-run after fix logged render_profile=x11-safe, gdk_backend=x11, display=:1, wayland_display=wayland-1, webkit_disable_compositing=1, gsk_renderer=cairo, libgl_always_software=1.
• Live relaunch after fix spawned PID 2776093 with gdk_backend=x11 and survived a one-minute process/log soak with no new compositor disconnect.
• bash -n packaging/launch-gravity-omega-native.sh
• node --check scripts/validate-scaffold.mjs
• npm run validate
• git diff --check origin/main...HEAD

Notes

• This is a follow-up to Harden Gravity Omega desktop launch freshness #27, which already fixed stale desktop binary launch evidence.
• Manual operator verification of chat typing is still the remaining human-visible check.
• Old Electron app and .sswp state were not touched.