Fix macOS dynamic SDL app bundling

[jeff-1amstudios]

Summary

• fix macOS dynamic SDL library discovery for app bundles
• bundle SDL2/SDL3 dylibs into the installed app and fix the bundle fixup/signing path
• use SDL pixel-art scaling for the SDL3 screen texture and add the libSDL3.dylib alias expected by the loader

SDL3 uses liner scaling by default so it was all blurry

[github-actions]

reccmp report

Saved diff report generated June 30 2026, 16:36:22 (16:11:27 ago)


Total effective accuracy 96.45% across 2387 functions (96.08% actual accuracy)
13 functions are aligned (0.54%)

[madebr]

Is this dmg file layout ok for macOS?

├── bin
│   └── Deth Race.app
│       └── Contents
│           ├── _CodeSignature
│           │   └── CodeResources
│           ├── Info.plist
│           ├── MacOS
│           │   ├── Deth Race
│           │   ├── libSDL2-2.0.0.dylib
│           │   ├── libSDL3.0.dylib
│           │   └── libSDL3.dylib -> libSDL3.0.dylib
│           └── Resources
│               └── dethrace.icns
└── share
    └── doc
        └── dethrace
            └── LICENSE

The bin and share/doc/dethrace should not be there.
The license file should be in the bundle.

[github-actions]

reccmp report

Saved diff report generated June 30 2026, 16:36:22 (1 day, 2:33:18 ago)


Total effective accuracy 96.45% across 2387 functions (96.08% actual accuracy)
13 functions are aligned (0.54%)

[madebr]

Is LICENSE placed correctly? Should it be in or outside the app bundle?

├── Deth Race.app
│   └── Contents
│       ├── _CodeSignature
│       │   └── CodeResources
│       ├── Info.plist
│       ├── MacOS
│       │   ├── Deth Race
│       │   ├── libSDL2-2.0.0.dylib
│       │   ├── libSDL3.0.dylib
│       │   └── libSDL3.dylib -> libSDL3.0.dylib
│       └── Resources
│           └── dethrace.icns
└── LICENSE