Smart contract for Loan approvals

**Goal:** Allow members to vote on loan requests transparently on-chain.

**Explanation:**
This automates group-based decision making.
Each member gets a vote. Votes are recorded immutably.

**Key Functions:**

- `requestLoan(uint amount)`

- `voteOnLoan(uint loanId, bool approve)`

- `finalizeLoan(uint loanId)`

**Deliverables:**

- `contracts/LoanVoting.sol`

- Emits `LoanApproved` or `LoanRejected`

- Test: quorum logic (≥50% yes votes)