fix(bounties): throw BadRequestException when releasing team bounty with empty splits

[moxiaoshen567]

Fixes #102

Summary

• In BountiesService.markMergedAndRelease, throw BadRequestException when an assigned team has zero member splits (!team || !team.splits || team.splits.length === 0) instead of silently skipping splitRelease and erroneously transitioning the bounty status to PAID.
• Added unit tests in src/bounties/bounties.service.spec.ts asserting:
  1. markMergedAndRelease throws BadRequestException and prevents escrow release / transition to PAID when team.splits is empty.
  2. markMergedAndRelease performs split release as expected when valid splits exist.

Verification

npx jest src/bounties/bounties.service.spec.ts
# 8 passed, 8 total (100%)
npx jest src/teams/ src/escrow/ src/github/
# 85 passed, 85 total across 10 test suites

/claim #102

💰 Payout Details

• USDC (Solana): 6UvBhyhY6ayeoJEGZxK4bDoFAHd9yeRDTVusnoDGdgQ5
• USDT (TRON / TRC20): TYcNrMSoY36q8WrsFSZyB26Rkj25EFgQsX

[vercel]

@moxiaoshen567 is attempting to deploy a commit to the chonilius' projects Team on Vercel.

A member of the Team first needs to authorize it.

[moxiaoshen567]

💰 Payout Details

• USDC (Solana): 6UvBhyhY6ayeoJEGZxK4bDoFAHd9yeRDTVusnoDGdgQ5
• USDT (TRON / TRC20): TYcNrMSoY36q8WrsFSZyB26Rkj25EFgQsX