[BACKEND] - Double elimination, round robin, and Swiss bracket generation are unimplemented stubs

[Hydrax117]

Description:
Three of the four supported bracket types are empty stubs that silently succeed without creating any rounds or matches:

async fn generate_double_elimination_bracket(...) -> Result<(), ApiError> {
    // TODO: Implement double elimination bracket
    Ok(())
}
async fn generate_round_robin_bracket(...) -> Result<(), ApiError> {
    // TODO: Implement round robin bracket
    Ok(())
}
async fn generate_swiss_bracket(...) -> Result<(), ApiError> {
    // TODO: Implement Swiss bracket
    Ok(())
}

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@Hydrax117 This issue could not be added to the Stellar Wave Program because the per-repo points budget would be exceeded (25000 / 25000 points already used). The label has been automatically removed.

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[iyanumajekodunmi756]

@iyanumajekodunmi756 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I would like to work on this issue

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[drips-wave]

Congratulations, @iyanumajekodunmi756! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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