Name the decoded-source cfg predicates with alias features

[LargeModGames]

Is your feature request related to a problem? Please describe.
About 80 #[cfg(any(feature = "local-files", feature = "subsonic", feature = "qobuz", feature = "youtube"))] attributes across some 20 files spell out "a queueable decoded source is compiled in" by hand, and the five-way variant with internet-radio is exactly feature = "audio-decode". Adding Qobuz meant editing every one of them (#489), and a missed list compiles fine but silently drops that source from one feature combination that no CI leg exercises.

Describe the solution you'd like
One implied feature in Cargo.toml, for example decoded-queue = [], listed inside local-files, subsonic, qobuz, and youtube. The four-way lists become #[cfg(feature = "decoded-queue")] and the five-way lists become #[cfg(feature = "audio-decode")]. A sixth source then touches Cargo.toml and nothing else.

Describe alternatives you've considered
Leaving the lists as they are; the next source repeats the same sweep.

Additional context
Mechanical, no behaviour change; from the review of #489.

[spotatui]

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Label: enhancement
Likely area: Cargo.toml feature configuration / build-time feature gating

Summary

The issue proposes replacing the long hand-written #[cfg(any(feature = ...))] attribute lists used to detect when a decoded queueable source is compiled in with a single implied Cargo feature alias. This would prevent source-specific feature lists from being incompletely updated, which can silently drop a source from certain feature combinations.

Key points

• Approximately 80 #[cfg(any(feature = "local-files", feature = "subsonic", feature = "qobuz", feature = "youtube"))] attributes exist across about 20 files.
• The five-way variant including internet-radio is exactly feature = "audio-decode".
• Adding Qobuz required editing every such occurrence (feat(sources): add Qobuz #489), and a missed list would silently drop that source from a feature combination not exercised by CI.
• Proposed solution: add an implied feature like decoded-queue = [] in Cargo.toml, listed inside local-files, subsonic, qobuz, and youtube; then use #[cfg(feature = "decoded-queue")] for f

Possible duplicates: none found

_{Compared against the 29 most recently updated open issues.}

[topongo]

i'm looking into it. will CI pipelines check for uncommon feature intersections? if not i will run them locally: changing so many feature gating directives is going to be risky

[LargeModGames]

i'm looking into it. will CI pipelines check for uncommon feature intersections? if not i will run them locally: changing so many feature gating directives is going to be risky

No, CI only compiles the decoded sources all at once (all-sources and macos), so please run cargo clippy and cargo test locally with each single source, with and without streaming, before you open the PR.