Duplicate filename detection is only relevant for LoRAs, which use
basename-only syntax (<lora:name:strength>). Checkpoints and diffusion
models reference files via relative paths with extensions, so filename
conflicts there are false positives — there is no resolution ambiguity.
Both _log_duplicate_filename_summary() and DoctorHandler's
_check_filename_conflicts() now skip scanners with model_type != 'lora'.