Replace onSurfaceCleanup with onSurfaceDestroyed

[Dreamersoul]

#580

[up-doc]

My android is broken on latest 2.9.1 until this is merged in.

Can we get this in a new version asap if possible?

[emakar]

onSurfaceDestroyed is deprecated
update to at least 3.29

[emakar]

may as well set minimal version for pdfx as 3.29

[vicajilau]

Thanks for the report and the fix. Digging into it, this only fixes half the problem: onSurfaceCleanup is available from Flutter 3.29, but onSurfaceAvailable (also overridden here) requires Flutter 3.27, and pdfx's pubspec still claimed a 3.24.0 minimum, which never compiled against either name. Opened #645 to raise the minimum to 3.29.0 instead, so both overrides are valid and match the version we actually support. Closing this in favor of that. Appreciate the pointer to the real issue (#580).