Whisper Input v1.3.20

Fixes the repeated Windows Right Alt regression by repairing legacy default RightAlt preferences that were left in Hold mode. On Windows, a stale default RightAlt + Hold configuration is migrated once to Toggle so a normal tap starts dictation instead of immediately stopping while ASR is still connecting. The migration is versioned so users can still intentionally choose Hold later. Adds full Windows AltGr sequence tests for trigger and shortcut recording, covering the synthetic left Ctrl + extended Right Alt sequence. Keeps the Windows hotkey regression CI in place for future main/PR changes.