System.dat pins the 2 KiB X1 font as xmil/IPLROM.X1T, where xmil reads
a 32 KiB Turbo IPL. A held copy of the exact size a profile declares now
proves its claim against a file of another size, so the existence packs
ship the IPL. The font's duplicate under the IPL name is removed.
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.