Add Option to Prioritize MAME Parent ROMs During Full-Set Import

📋 Summary

Add an option to the MAME Full Set Importer that lets users prioritize the MAME-defined parent ROM as the default version of a game.

❗ Problem

When importing a MAME full set, LaunchBox currently uses region and variant preferences to help choose the primary version when related parent/clone sets are grouped.

That works well for many users, but some users prefer the default version to match the parent ROM defined by MAME itself, regardless of region or player-count preferences.

💡 Proposal

Add a checkbox or advanced option to the MAME Full Set Importer, such as:

• Prioritize MAME parent ROMs

• Prefer parent ROM as default version

When enabled, LaunchBox would use the MAME-defined parent ROM as the main/default version when importing grouped MAME games.

If the parent ROM is unavailable or not working, LaunchBox could fall back to the existing region and variant priority behavior.

🧩 Use Cases

• Keep imported MAME games aligned with MAME’s parent/clone structure

• Make the parent set the default launch option

• Avoid a clone becoming the primary version when the user prefers the parent

• Still allow region/variant preferences as a fallback when needed

📦 Benefits

• Gives users more control over MAME import behavior

• Better supports users who organize around parent sets

• Preserves existing region/variant behavior for users who prefer it

• Reduces manual cleanup after importing full MAME sets

⚠️ Considerations

This should be optional and should not replace the existing region and variant priority options. The current behavior should remain available for users who prefer regional or player-count prioritization.