Expand isSupported check to allow alternative codecs

[robwalch]

This PR will...

• Expand isSupported check to test alternate baseline codecs. At least one isTypeSupported check must pass for isSupported to return true
  • (Resolves Update isSupported for browsers without MPEG-LA licensed codecs #6004)
• Add isMSESupported check (checks for MediaSource API without isTypeSupported checks)
• Add named exports for and expose statically: isSupported, isMSESupported, and getMediaSource
  • (Resolves Missing "./src/is-supported" specifier in "hls.js" package. (svelte, vite) #5593)

Why is this Pull Request needed?

Not all platforms support AVC/AAC via MSE.

Applications needing more fine grained support checks based on expected delivery formats can implement those checks in their app layer using isMSESupported and getMediaSource().isTypeSupported(mimeType).

Are there any points in the code the reviewer needs to double check?

Ideally the list of codecs checked will be kept short. It should only contain the most widely supported codecs required for compatibility. Changes can be contributed given specific device or platform specifications that demonstrate the need for such a change.

Resolves issues:

Resolves #6004, #5593

Checklist

• changes have been done against master branch, and PR does not conflict
• new unit / functional tests have been added (whenever applicable)
• API or design changes are documented in API.md