Add CD-i (Philips CD-Interactive) support

[wizzomafizzo]

Summary

Add support for identifying CD-i (Philips CD-Interactive) games.

Background

The Philips CD-i (1991) was a multimedia CD player that also played games. It uses standard CDs with a modified ISO 9660 filesystem known as the "Green Book" format.

Technical Details

• Media type: Standard CD (Green Book format)
• Filesystem: Modified ISO 9660
• Detection signatures:
  • " CD-I " (with trailing space) at byte 1 of Primary Volume Descriptor
  • "CD-RTOS" string in volume descriptor
• Identification fields:
  • Application identifier field contains game info
  • Volume label

Proposed ID Method

1. Detect CD-i format via " CD-I " signature in PVD
2. Extract application identifier for game identification
3. Use volume label as fallback/secondary identifier

Implementation Notes

• Can mostly reuse existing ISO9660 parsing
• Need to check for CD-i signature at PVD offset 1
• Application identifier parsing may need custom handling

Compatibility

• ✅ Readable by standard CD/DVD drives
• Moderate difficulty implementation
• Clear detection signature makes format identification reliable