Should be able to check if the index in the caret position is valid in the ctor.

[andy840119]

For example, here's the TimeTagCaretPosition. Need to :

• Check if TimeTag is in the Lyric
• Also, add valid index and invalid index check in the shared test case.
• CompareTo should check the index of time-tag in the lyric, not compared by index.

[andy840119]

[Update]

1. The change index out of range logic is already in the CaretPositionAlgorithm.PositionMovable().
2. It might be possible to give the caret position in the caret position algorithm. Using try-catch in the algorithm is not a good idea.
3. check the check-caret-index-is-valid-in-caret-position in my repo.