Move 17 case-colliding BIOS variants to .variants/ so Windows
and macOS clones no longer lose files. Existence-based platforms
keep the primary, MD5-based platforms resolve from .variants/.
Also fix resolve_local_file zipped_file resolution: when multiple
ZIPs share a name, verify the inner ROM exists before accepting
a candidate. Fixes adam_fdc.zip resolving to the wrong archive.
shared groups in _shared.yml: np2kai, keropi, quasi88, kronos, ep128emu
with source references for each subdirectory requirement.
libretro_scraper: CORE_SUBDIR_MAP applies subdirectory prefixes at
generation time (np2kai/, keropi/, dc/). EXTRA_SYSTEMS adds QUASI88.
SYSTEM_SHARED_GROUPS injects includes for kronos/np2kai/keropi.
new BIOS: CPS3 (23 ZIPs), Cannonball OutRun (40 ROMs), PCem PC BIOS
(73 files), VICE Commodore ROMs, Spectrum ZIPs, dc_bios.bin, X1 fonts.
new emulator profiles: redream, melonds_ds, lrps2 with doc vs source
notes. platforms/README.md documents shared groups architecture.
New files: OpenTyrian data (11), Cave Story (2), SeaBIOS,
VGA BIOS, OpenSBI, Cromwell, xbox_hdd, Sega CD Model 2 (3),
NGP Color BIOS, Pentagon 128p-1.rom, X1 font, BK TERAK.
cross_reference.py: basename + case-insensitive lookup.
