(Update) Change mediainfo to longtext

[Obi-Wana]

Some special cases (e.g., many subtitles) cause the mediainfo to become larger than text can store. The next bigger type should fix this.

[what-the-diff]

PR Summary

• Update of Media Information Storage Capacity
  The section for storing media information in the 'torrents' table is revamped, allowing for more extensive information to be stored.
• Improved Flexibility in Data Management
  Incorporated a method making column alterations reversible, ensuring effective management and prevention of data loss in case of any undesired changes.

[HDVinnie]

Thanks.