feat: Select default track by a list of preferences

[KimKyuHoi]

I went ahead and implemented the full structured preference system that was discussed in #1591.
Instead of just expanding languages to arrays, I replaced all 14 individual preference fields with 3 structured arrays:

  preferredAudio (language, role, label, channelCount, codec, spatialAudio)
  preferredText (language, role, format, forced)
  preferredVideo (label, role, codec, hdrLevel, layout)

Each array entry works as an AND filter - so you can say things like "I want Korean with 5.1 surround, but if not available, English is fine too":

player.configure('preferredAudio', [
  {language: 'ko', channelCount: 6},
  {language: 'ko'},
  {language: 'en'},
]);

Config - Replaced the 14 individual fields with 3 arrays of typed preference objects (AudioPreference, TextPreference, VideoPreference). The old fields still work at runtime with a deprecation warning, so existing apps won't break immediately.

Demo - The demo config UI now shows inline expandable preference lists instead of flat text inputs. You can add/remove entries and configure each field per entry. URL hash serialization was updated to use JSON format, with legacy param fallbacks preserved.

[avelad]

Related to #1591

[shaka-bot]

Incremental code coverage: 71.76%

[tykus160]

FYI there was a discussion in topic linked and instead of your proposal, we were thinking about more configurable objects, see #1591 (comment), #1591 (comment) & #1591 (comment)

[matvp91]

I appreciate the effort, but I'm not confident this would hold up over time. I would strongly prefer reducing the set of streams using a list of preferences (see the linked comments from @tykus160).

Allowing multiple languages introduces questions around multiple roles, codecs, and their possible combinations. The recent text track simplification likely makes integration more straightforward. We should be careful introducing this as a proper v5 API as we'll have to maintain backwards compatibility for a while.

@KimKyuHoi, would you be willing to experiment with the proposed idea's in #1591 as opposed to solely allowing multiple languages?

[KimKyuHoi]

@matvp91 Ah, I totally misunderstood (@avelad comment)! I thought that meant I had to maintain backwards compatibility. Thanks for clarifying that it's a breaking change release. That definitely makes the implementation simpler/cleaner. I will proceed without supporting the legacy config.

[matvp91]

Yes, we can break backwards compatibility with the introduction of a next major version.

I'm sorry I'm expanding scope so much for a change that should be relatively straight forward, but I feel we shall take advantage of the fact that we're going to bump a major version in order to get track preferences right from the get go. Nonetheless, we're here to help.

@tykus160, do you think implementing this in shaka.media.PreferenceBasedCriteria is a good strategy?

I'd love to hear everyone else's opinion though!

[KimKyuHoi]

@matvp91 I think it's a good suggestion. Then, why don't we open a new issue, create a relation, and proceed further? I'm making this suggestion because I'm going to be taking charge of it anyway. I was concerned that if we proceeded with the existing PR, the resulting diff files would be too large.

[matvp91]

@KimKyuHoi what works best for you, I'm OK either way.

[KimKyuHoi]

@matvp91 Oh, you've been waiting a long time, right? Sorry. I'll work on this repo.

[avelad]

Please update PR title and descripcion with the new changes.

[shaka-bot]

Bundle Size Report for PR #9542

File	HEAD	Base	Diff
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controls.css	23.3 KiB (4.9 KiB)	23.3 KiB (4.9 KiB)	0.0 KiB
demo.compiled.debug.js	244.3 KiB (49.1 KiB)	240.0 KiB (48.3 KiB)	+4.2 KiB
demo.compiled.js	244.3 KiB (49.1 KiB)	240.0 KiB (48.3 KiB)	+4.2 KiB
demo.css	170.3 KiB (27.8 KiB)	169.9 KiB (27.7 KiB)	+0.4 KiB
locales.js	42.6 KiB (10.6 KiB)	42.6 KiB (10.6 KiB)	0.0 KiB
receiver.compiled.debug.js	144.0 KiB (23.8 KiB)	144.0 KiB (23.8 KiB)	0.0 KiB
receiver.compiled.js	144.0 KiB (23.8 KiB)	144.0 KiB (23.8 KiB)	0.0 KiB
shaka-player.compiled.debug.js	1494.7 KiB (341.9 KiB)	1492.7 KiB (341.1 KiB)	+2.0 KiB
shaka-player.compiled.js	750.2 KiB (242.9 KiB)	748.3 KiB (242.2 KiB)	+1.9 KiB
shaka-player.dash.debug.js	1093.7 KiB (255.5 KiB)	1091.8 KiB (254.9 KiB)	+1.9 KiB
shaka-player.dash.js	516.2 KiB (170.9 KiB)	514.4 KiB (170.4 KiB)	+1.8 KiB
shaka-player.experimental.debug.js	1876.9 KiB (422.0 KiB)	1874.9 KiB (421.2 KiB)	+2.0 KiB
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shaka-player.hls.debug.js	1129.8 KiB (261.5 KiB)	1127.9 KiB (260.8 KiB)	+1.9 KiB
shaka-player.hls.js	553.8 KiB (182.3 KiB)	552.1 KiB (181.7 KiB)	+1.8 KiB
shaka-player.ui.debug.js	1815.9 KiB (409.0 KiB)	1813.9 KiB (408.2 KiB)	+2.0 KiB
shaka-player.ui.js	959.4 KiB (299.5 KiB)	957.5 KiB (298.8 KiB)	+1.9 KiB

[avelad]

@KimKyuHoi Please update the description of the PR to match with the current implementation!