Fix panmixer test for stereo (#17)

- also include reduced test action name
- added badge for tests

update to go 1.24, fix OPL voice playback (#15)

* update to go 1.24, fix opl voice playback

* update opl2 module to 1.0.2

Merge pull request #14 from heucuva/reintroduce-mixing

Reintroduce gomixing back into playback package

Merge pull request #12 from heucuva/cleanup-generics

Major rewrite

Merge pull request #8 from heucuva/api-cleanup

Updating gomixing package

Merge pull request #6 from heucuva/mixing-flatting-update

Update mixing package

Merge pull request #5 from heucuva/premix-cleanup

More cleanup

Merge pull request #4 from heucuva/feature-conversion

Lots of changes

Merge pull request #3 from heucuva/reintregrate-voice

Reintegrate voice package back into playback

Merge pull request #2 from heucuva/beta-cleanup

Beta cleanup