prod-romasplat-demo

Production package layout:
- romasplat_prod.exe: dedicated executable compiled for this demo
- data/assets.pack: packed external assets selected for this package
- data/assets_manifest.txt: logical-to-published asset path map
- data/romasplat/romasplat_settings.txt: demo-specific shipped configuration inside the asset pack
- manifest.json: package metadata

This production package disables the Dear ImGui development overlay and settings
file writes, but it loads the shipped demo configuration through the asset
manifest and asset pack. The next size step is to embed or append the pack to
the executable.
