Allow the sync command to scrape the data of already existing songs in the syncing directory for download data

[LunarN0v4]

Requested Feature

Make the sync command, maybe with a flag or by default, scrape the data of songs that have already been downloaded in the syncing directory for download data, making the creation of sync files way faster and (if there is songs which were downloaded by manually inputting a download link) making it easier for the user to resync all their songs from said sync file knowing everything was downloaded from the right sources.

Possible implementation

Make it so the data of every song in the output directory is scraped for the required data as the sync file is created, and adding that data as needed

[LunarN0v4]

By extension, I am asking that a new field is added to the sync file JSON format for this purpose.