Add user‑editable key and meter settings (similar to existing bar alignment feature)

Chordify already offers a very useful feature to correct misaligned bars, which helps a lot when the automatic analysis shifts the first measure.

I would like to suggest extending this concept to two additional musical fundamentals:

• Key correction: Allow users to set or adjust the detected key (e.g., when a song is analyzed in F major although the original is in B♭ major).

• Meter correction: Allow users to change the time signature (e.g., from 4/4 to alla breve / 2/2 for fast foxtrot or march‑style songs).

These elements are just as essential as bar alignment, and giving users the ability to correct them would significantly improve accuracy and usability for musicians.

Thank you for considering this enhancement!