Mods/OS Test Builds

Test builds for future library and packaging changes based on the current stable release. [b]Based on FSO 24.0.0[/b] Contains builds for: [ul] [li]Windows x86[/li] [li]Windows x64[/li] [li]Windows arm64[/li] [li]Linux x64[/li] [li]Linux arm64[/li] [li]macOS x64[/li] [li]macOS arm64[/li] [/ul] Library/packaging changes: [ul] [li]Upgrade to SDL 2.26.5 on all platforms[/li] [li]Add libs for Windows arm64[/li] [li]Use prebuilt ffmpeg, SDL2, and OpenAL libs on Linux[/li] [/ul] Contains the following additional changes from stable: [ul] [li]Windows arm64 support (no PR)[/li] [li]fix time-to-goal edge cases (#5943)[/li] [li]Fix SSM strikes with a variable count. (#5993)[/li] [li]fix "this ship name is already in use" bug (#5996)[/li] [li]Fix broken collision pair caching (#6007)[/li] [li]Fix message api out of bounds check (#6013)[/li] [li]Fix CTD with HUD Preset Switching (#6022)[/li] [li]add support for decompression of DDS textures (#6025)[/li] [li]limit debug log spam from file shadows (#6027)[/li] [li]clean up and update macOS bundle info (#6028)[/li] [li]Fix crash when right-clicking on a container modifier (#6030)[/li] [li]Handle container data nodes correctly with eval_num() (#6031)[/li] [/ul]