debug: Add IMDb ID detection logging and database-first optimization

Added comprehensive debugging for IMDb ID detection to identify issues
with directories that don't have IMDb IDs in folder names but do have
them in filenames (like Adulthood (2025) [tt26657977]).

Also added database-first optimization that skips expensive API calls
when we already have complete data in the database. This should:
- Speed up full rescans significantly
- Reduce unnecessary API calls to TMDB/OMDB/Radarr
- Keep database size appropriate by not re-querying known movies

This should resolve both the small database size issue and improve
performance for movies that already have valid dateadded entries.

nfoguard.py

@@ -974,6 +974,25 @@ class MovieProcessor:
         existing = self.db.get_movie_dates(imdb_id)
         _log("DEBUG", f"Database lookup for {imdb_id}: {existing}")
         
+        # If we have complete data in database, use it and skip expensive API calls
+        if existing and existing.get("dateadded") and existing.get("source") != "no_valid_date_source":
+            _log("INFO", f"✅ Using complete database data for {imdb_id}: {existing['dateadded']} (source: {existing['source']})")
+            # Still create NFO and update files but skip API queries
+            dateadded, source, released = existing["dateadded"], existing["source"], existing.get("released")
+            
+            # Create NFO with existing data
+            if config.manage_nfo:
+                self.nfo_manager.create_movie_nfo(
+                    movie_path, imdb_id, dateadded, released, source, config.lock_metadata
+                )
+            
+            # Update file mtimes if enabled
+            if config.fix_dir_mtimes and dateadded:
+                self.nfo_manager.update_movie_files_mtime(movie_path, dateadded)
+            
+            _log("INFO", f"Completed processing movie: {movie_path.name} (source: {source}) [database-only]")
+            return
+        
         # Handle webhook mode - prioritize database, then use proper date logic
         if webhook_mode:
             _log("DEBUG", f"Webhook mode: existing={bool(existing)}, has_dateadded={bool(existing and existing.get('dateadded')) if existing else 'N/A'}")