Use JSON file for match mode configs [AARD-2086]

[rutmanz]

Task

AARD-2086

Symptom

Currently default match mode configs are defined in-code, which means that updating the list (as would be necessary on kickoff) would require a redeploy of synthesis

Solution

This changes them to be defined by a JSON file in the assetpack, which is loaded on startup

Verification

Check that the configurations still show up and work correctly
This does change the assetpack, so you'll have to run bun run assetpack before testing

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• All acceptance criteria outlined in the ticket are met.
• Necessary test cases have been added and updated.
• A feature toggle or safe disable path has been added (if applicable).
• User-facing polish:
  • Ask: "Is this ready-looking?"
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  • PR links to the relevant Jira issue.
  • Jira ticket has a comment referencing this PR.

[ryanzhangofficial]

makes sense!

[AlexD717]

Looks good, just a very small nitpick