* fix: resolve Apple Silicon bandwidth variants
* fix(hwfit): preserve string lookup path in _lookup_bandwidth
* fix(hwfit): guard Apple bandwidth lookup against false GPU matches
Add "apple" not in gn check to _lookup_apple_bandwidth() so that
non-Apple GPUs with "m3"/"m4"/"m5" in their names (e.g. NVIDIA
Quadro M4 000) don't incorrectly match Apple bandwidth tiers.
Addresses @o3LL review comment on PR #2564.
Ahmad Naalweh