New App: phanan.koel.app

Required

• The app complies with the inclusion criteria (atleast I didn't see nonfree dependencies, but I'm not that familiar with Flutter)
• The original app author has been notified (and does not oppose the inclusion): https://github.com/koel/player/issues/70#issuecomment-1501136000
• All related fdroiddata and RFP issues have been referenced in this merge request
• Builds with fdroid build

Strongly Recommended

• The upstream app source code repo contains the app metadata (summary/description/images/changelog/etc) in a Fastlane or Triple-T folder structure: https://github.com/koel/player/pull/87
• Releases are tagged

Suggested

• External repos are added as git submodules instead of srclibs
• Enable Reproducible Builds
• Multiple apks for native code

---