SGDK project

Help the developer get a normal SGDK project building. Use the container for the toolchain and keep source files on the host. Do not introduce a game engine or replace an existing build system as part of setup.

Establish the project

1. Inspect existing source, resource files and Makefiles. Preserve the project's structure and conventions.
2. Use ewrogers/sgdk:latest, as described in the Docker workflow. Prefer its native architecture; do not force AMD64 on an ARM64 machine.
3. Run doctor and check the relevant headers, resource manual and upstream sample before writing unfamiliar SDK calls. Use actual declarations and comments, not a remembered API from another release or engine.