The menu generation was failing because it tried to use "IBM Plex Mono"
font which isn't universally available. FFmpeg's drawtext filter would
fail silently when the font didn't exist.
Changes:
- Check if FontPath actually exists before using it (os.Stat check)
- Only use FontName if it's a known universally available font
- Whitelist of safe fonts: DejaVu, Liberation, Free fonts
- Ultimate fallback: "monospace" (most universally available)
Before:
- Tried IBM Plex Mono (not installed) → FFmpeg fails → "ERROR: FFmpeg failed during DVD encoding"
After:
- Tries IBM Plex Mono font file → doesn't exist
- Checks if "IBM Plex Mono" is in safe list → not in list
- Falls back to "monospace" → works everywhere
This fixes the cryptic "FFmpeg failed during DVD encoding" error that
actually occurred during menu generation, not encoding.
- Fix unterminated string in author_menu.go line 418
- Fix invalid escape sequences in escapeDrawtextText function
- Remove orphaned code outside function body in main.go
- Fix extra parentheses causing syntax errors
- Ensure clean compilation for successful build
- Refactor author_menu.go to support multiple menu templates
- Add Simple, Dark, and Poster menu templates
- Add UI for selecting menu template and background image
