Update vcpkg baseline and CI configuration for improved compatibility

- Changed the builtin baseline in vcpkg.json to a specific commit hash for better dependency management.
- Updated CI workflow in ci.yml to use GCC-12 and Clang-15, enhancing compiler support and ensuring compatibility with the latest features.
- Added necessary packages for the new compiler versions to the CI setup, improving build reliability.

vcpkg.json

@@ -7,5 +7,5 @@
     "libpng",
     "sdl2[core]"
   ],
-  "builtin-baseline": "2024.12.16"
+  "builtin-baseline": "c8696863d371ab7f46e213d8f5ca923c4aef2a00"
 }