[onyekachi66]

Closes #1309

Objective

Improves BridgeWise's cross-chain routing and execution platform by implementing and verifying access-control role revocation behavior, enforcing strict asset and chain boundaries, eliminating duplicate/unsafe execution, and exposing actionable diagnostic evidence for operators without logging sensitive secrets or transaction payloads.

Scope & Key Changes

• Smart Contract (contracts/BridgeCoreAccessControl.sol):
  • Implements OpenZeppelin UUPS-upgradeable access control with distinct operational roles: DEFAULT_ADMIN_ROLE, OPERATOR_ROLE, EXECUTOR_ROLE, and ROUTER_ROLE.
  • Added verifyRoleRevocation(bytes32 role, address account) restricted to OPERATOR_ROLE to verify and emit RoleRevocationVerified evidence for auditability during incidents or maintenance.
  • Reverts with RoleNotRevoked(bytes32 role, address account) if an unrevoked role is queried.
  • Enforces transfer idempotency via executedTransfers bitmap/mapping, reverting duplicate executions with custom error TransferAlreadyExecuted(bytes32 transferId) and emitting ExecutionAttemptRejected.
  • Validates recipient and non-zero amount boundaries to protect assets.
  • Reserved a 50-slot storage gap (uint256[50] private __gap) to safeguard upgrade compatibility.
• Contract Tests (contracts/test/BridgeCoreAccessControl.spec.ts):
  • Validates authorized transfer execution and unauthorized caller rejection (AccessControlUnauthorizedAccount).
  • Verifies parameter boundary enforcement (zero address recipient, zero amounts).
  • Asserts duplicate execution rejection and idempotency diagnostics.
  • Validates immediate revocation enforcement upon admin role revocation.
  • Tests verifyRoleRevocation success and revert behavior when roles remain active.
  • Asserts role and state preservation across UUPS proxy upgrades, plus unauthorized upgrade rejection.
• Documentation (docs/VERIFY_ACCESS_CONTROL_ROLE_REVOCATION.md):
  • Documents public interfaces, role semantics, gas and resource impact, UUPS upgrade considerations, and operator recovery/escalation paths.

Acceptance Criteria Verification

• Contract-level tests assert relevant invariants and reject unauthorized or malformed calls.
• Gas/resource impact and upgrade implications are documented.
• Public interfaces, configuration, and failure semantics are documented.
• Unit and boundary tests cover success, boundary, invalid-input, and failure cases.
• Logs and metrics are actionable and exclude secrets, private keys, and sensitive payloads.
• Pushed to upstream branch feat/verify-access-control-role-revocation using local git configuration.