Refactor Database and File modules to improve data handling

Update the Database class to include explicit methods for fetching
various entity types, managing relationships, and querying file paths.
Implement hashing logic in the File module to facilitate tracking by
unique identifiers. Add C++20 support in configuration files.

include/Containers.h

@@ -34,6 +34,7 @@ struct Track {
     std::string artwork;
     TagLib::String genre;
     std::string format;
+    uint64_t hash;
 };
 
 using trackPtr = std::shared_ptr<Track>;