feat: add net10 support while retaining net9 and net8 compatibility

[kimpenhaus]

what changed

• added net10 target to project multi-targeting and adjusted conditional compilation where necessary
• updated ci/workflow to build and test for net10, net9, and net8
• preserved runtime behaviour and public apis for net9 and net8
• applied minor fixes and conditional code paths to address api differences introduced in net10

compatibility & migration notes

• multi-targeting preserves compatibility across net8, net9, and net10
• no breaking api changes introduced by this pr
• consumers targeting older frameworks should require no changes
• if consumers rely on framework-specific behaviour, validate in your environment using net10

[kimpenhaus]

this should also include package updates from #984 and #992