Why not enforce the segment availability duration *should* only be set for live?

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Not applicable

What version of Shaka Player are you using?

v4.16.29, v5.0.28

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Chrome Windows 11, Edge Windows 11, Chrome MacOS

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I've been trying to debug a strange issue when playing an In Progress Recording "Startover" stream whereby I regularly see the assertion failure from Presentation Timeline: https://github.com/shaka-project/shaka-player/blob/bf7ea8dc386991fd84963df8eb5e271b046082fa/lib/media/presentation_timeline.js#L789

It is because segmentAvailibilityDuration_ is a finite number which has been set by the DASH Parser from

    let segmentAvailabilityDuration = TXml.parseAttr(
        mpd, 'timeShiftBufferDepth', TXml.parseDuration);

Presentation Timeline has number of comments about "... should only be...". https://github.com/shaka-project/shaka-player/blob/bf7ea8dc386991fd84963df8eb5e271b046082fa/lib/media/presentation_timeline.js#L209

In this case a number of calculations misinterpreted results in seekable start wobbling from zero up to a few seconds. This seems wrong and I fear is the root cause of a issue at hand.

Why not close down this vulnerability?