Sync lyrics to audio

This is the main job. Load the track you're syncing against, get every lyric line into the editor, then stamp each line's timestamp in real time while the song plays. The sub-sections below walk that flow from loading a file to fine-tuning a finished sync.

A quick end-to-end pass looks like this: open the music, paste your lyrics into the Notepad and push them into the list, click the first line, press Play, and tap the sync key as you hear each line. When you reach the end, save the .lrc.