Voice note's duration is not persisted.

### Problem

Currently we’re not storing a Voice note’s duration to storage.
Meanwhile, we want to show the duration of a recording in the Note list/Recording detail view.

### Solution.

There're 2 potential approaches:

- [x] 1. We extract duration information from voice note file whenever we need it.
- [ ] 2. Persist Voice's note duration in `cache storage` of ARK framework.

For MVP, we'll go with 1st approach.
For post MVP, we'll go with 2nd approach when `cache storage` is ready to be used.