PraseTja: Add branches

- Needs the following changes to the database: change `easy`, `normal`, `hard`, and `oni` to `TEXT` type
- When adding songs to the database and if, for example, a song's 7-star difficulty has a branch, instead of `7` input `7 B`, this is to display song's branch support on the song selection
- Branch can be forced in debug

public/src/js/canvasdraw.js

@@ -1167,6 +1167,7 @@
 		var firstTop = config.multiplayer ? 0 : 30
 		var secondTop = config.multiplayer ? 0 : 8
 		
+		config.percentage = Math.max(0, Math.min(1, config.percentage))
 		var cleared = config.percentage - 1 / 50 >= config.clear
 		
 		var gaugeW = 14 * 50