Add contract test: complete group lifecycle with 5 members

[big14way]

End-to-end test with a realistic group size.

Acceptance Criteria:

• Create group with 5 members
• Complete all 5 rounds with contributions and payouts
• Verify each member received exactly once
• Verify final balances are correct
• Verify group status is Completed

Files: contracts/sorosave/src/test.rs

[WuXieSec]

/attempt #32

I can deliver this quickly.

Plan:

1. Build a full 5-member lifecycle test (create -> join -> start -> multi-round contributions -> payouts -> completion)
2. Verify final invariants (status, balances/payout order, no stuck funds)
3. Run "cargo test --package sorosave" in ephemeral Rust env and submit PR

Payout preference: PayPal (wuxiesec@gmail.com) after merge verification.

[WuXieSec]

Update: withdrawing my attempt on this issue for now. Please feel free to reassign/open to other contributors.

[Scottcjn]

Implemented in PR #84: #84

This adds a 5-member end-to-end lifecycle test that:

• creates and fills a 5-member group
• runs all 5 rounds
• verifies the payout order covers each member exactly once
• checks each round reaches the expected contribution total
• asserts final balances return to the starting value

Verified locally with cargo test.