fix: Inaccurate duration on Android

[Colton127]

Description

Resolves an issue where the recorded duration reported is twice the real value on Android.

Checklist

• The title of my PR starts with a Conventional Commit prefix (fix:, feat:, docs: etc).
• I have followed the Contributor Guide when preparing my PR.
• I have updated/added tests for ALL new/updated/fixed functionality.
• I have updated/added relevant documentation in docs and added dartdoc comments with ///.
• I have updated/added relevant examples in examples or docs.

Breaking Change?

• Yes, this PR is a breaking change.
• No, this PR is not a breaking change.

Related Issues

Closes #476

[lavigarg-simform]

Thanks for tracking this down and submitting a fix, @Colton127!

This PR and PR #494 address the same root bug — totalSamples counting bytes instead of samples, causing onCurrentDuration to report 2× the real elapsed time on Android.

We’re going to proceed with the other PR instead as the primary fix because it derives bytesPerSample from the actual audioFormat (handling 8-bit and float PCM, not just the common 16-bit case).

However, your PR contributed one important thing that will be carried forward into that PR:

• The diagnosis of the totalSamples reset placement (stop() → startRecording()), which also addresses the near-zero duration value emitted after stop.

Closing this in favour of #494. Thanks again for the contribution!