Read the terminal-page bound a fetched page reports, AniList's
pageInfo.lastPage, so numeric look-ahead scheduling can stop launching
pages the server has already said do not exist. AniList page traversals
pass this as the look-ahead driver's extractBound; chunk traversals
supply no bound reader. Returns undefined when
the response carries no usable bound (a non-object payload, a missing or
malformed pageInfo, or a lastPage that is not a positive finite number,
such as the 0 AniList reports when the true count is unknown), leaving
scheduling to the existing terminal-entry and guard checks.
Parameters
response: unknown
A fetched page response of any shape.
Returns number|undefined
The positive lastPage bound reported by the page, or undefined when unknown.
Read the terminal-page bound a fetched page reports, AniList's
pageInfo.lastPage, so numeric look-ahead scheduling can stop launching pages the server has already said do not exist. AniList page traversals pass this as the look-ahead driver'sextractBound; chunk traversals supply no bound reader. Returnsundefinedwhen the response carries no usable bound (a non-object payload, a missing or malformedpageInfo, or alastPagethat is not a positive finite number, such as the0AniList reports when the true count is unknown), leaving scheduling to the existing terminal-entry and guard checks.