fix: add psx variant mappings, fix emulator verify path

scph3000.bin v2.1J and scph3500.bin v2.2J already existed under
different primary names (scph3500.bin and scph5000.bin respectively).
Add .variants/ entries so by_name resolves both filenames.

verify_single_emulator now calls _find_best_variant on hash mismatch,
matching the platform-level verification path.

scripts/verify.py

@@ -1230,6 +1230,17 @@ def verify_emulator(
                 check = check_file_validation(local_path, name, validation_index)
                 if check:
                     reason, _emus = check
+                    better = _find_best_variant(
+                        file_entry, db, local_path, validation_index,
+                    )
+                    if better:
+                        result = {
+                            "name": name,
+                            "status": Status.OK,
+                            "required": required,
+                            "path": better,
+                        }
+                    else:
                         result = {
                             "name": name,
                             "status": Status.UNTESTED,