refactor: consolidate CI pipeline, remove third-party deps

scripts/common.py

@@ -7,6 +7,7 @@ and file resolution - eliminates DRY violations across scripts.
 from __future__ import annotations
 
 import hashlib
+import json
 import os
 import zipfile
 import zlib
@@ -38,6 +39,12 @@ def compute_hashes(filepath: str | Path) -> dict[str, str]:
     }
 
 
+def load_database(db_path: str) -> dict:
+    """Load database.json and return parsed dict."""
+    with open(db_path) as f:
+        return json.load(f)
+
+
 def md5sum(filepath: str | Path) -> str:
     """Compute MD5 of a file - matches Batocera's md5sum()."""
     h = hashlib.md5()