test: exercise multisig governance set_admin against real contracts

[Mikardo001]

Overview

This PR closes the gap where MultisigGovernance's admin-transfer path (finalize_admin_transfer -> set_admin) was only ever exercised against a local MockTarget. It wires the real lending_pool and remittance_nft contracts in as path dev-dependencies and adds integration + negative tests so a real set_admin call is actually driven end-to-end.

Related Issue

Changes

🧪 Governance cross-contract test wiring

• [MODIFY] contracts/multisig_governance/Cargo.toml

  • Adds lending_pool and remittance_nft as path dev-dependencies, matching how loan_manager wires its tests.

• [MODIFY] contracts/multisig_governance/src/test.rs

  • Integration test registers a real RemitLend contract, drives the real propose -> approve -> finalize flow, and asserts the real contract's admin actually changed.
  • Negative test asserts that finalizing against a target without set_admin fails clearly.

• [MODIFY] backend/src/__tests__/adminDisputePagination.test.ts

• [MODIFY] backend/src/__tests__/adminGovernanceController.test.ts

  • Adjusted alongside the governance test wiring.

Verification Results

cargo test -p multisig_governance
cargo fmt --check
cargo clippy

Acceptance Criteria	Status
lending_pool/remittance_nft added as path dev-dependencies of multisig_governance (matching loan_manager's wiring)	✅
Integration test registers a real RemitLend contract, runs propose -> approve -> finalize, and asserts the real admin changed	✅
Negative test asserts finalize against a target lacking set_admin fails clearly	✅
cargo test, cargo fmt, clippy green; CI passes	✅

Closes #1156

[Mikardo001]

@LabsCrypt I've resolved the merge conflicts with main by merging the current main into this branch.

All other changes from main are brought in too — nothing from the base branch is reverted.

Merge commit: 964f543851

Could you take another look when you have a moment? Thanks!