Flashback Turbo - быстрый экспорт видео из реплеев Flashback

Fix the 0.3.0 export bug + re-enable H8

0.3.0's H8 Mixin had an invalid @At("THROW") annotation which caused the entire ExportJobProgressMixin to fail to apply with InvalidInjectionException. The error was at Mixin parse time, before our code could even run, and broke the export pipeline.

This release:

• Removes the invalid @At("THROW") and uses @At("TAIL") for cleanup (covers normal returns; if export throws, the screen stays — minor cosmetic, will close on next user interaction).
• Sets setScreen() synchronously instead of via mc.execute() to avoid timing issues with Flashback's internal setScreen(null) calls.
• Re-enables showExportProgressOverlay by default.

The overlay should now display correctly during exports without breaking them. If you still hit issues, toggle showExportProgressOverlay = false in config/flashbackturbo.json to revert to vanilla behavior.

Apologies again for the 0.3.0 regression.