[arifrhm]

Fixes #156

Summary

Adds parameterized fuzz invariants to test/integration/Invariants.t.sol to provide automated production release gates and property-based verification beyond fixed-amount unit tests:

1. testFuzz_unregisteredVenue_adapterNotRegistered:

   • Asserts that for any arbitrary unmapped venue address, the router strictly reverts with Errors.AdapterNotRegistered before dispatching or mutating any state.

2. testFuzz_nonceReplay_nonceUsed:

   • Asserts that for any arbitrary bounded amount (1 ether to 100 ether) and arbitrary uint64 nonce, the initial swap succeeds and replaying the identical caller + nonce tuple strictly reverts with Errors.NonceUsed.

3. testFuzz_nonCustodial_zeroBalancesAfterSwap:

   • Validates the fundamental non-custodial invariant across all bounded swap amounts: post-swap, both the ExecutionRouter and ExecutionAdapter hold strictly zero balances of both the incoming quote token and outgoing RWA token.

4. testFuzz_suspendedVenue_blocks:

   • Validates that when an emergency kill-switch is triggered (setVenueSuspended), all subsequent execution attempts across any arbitrary amount strictly revert with Errors.VenueSuspended.

Verification & Quality Checks

• All 10 tests in InvariantsTest pass (forge test --match-contract InvariantsTest -vv): 256 fuzz runs each, 0 reverts/failures.
• All 912 tests across the repository pass (forge test).
• Code formatting verified with forge fmt.
• Only test/integration/Invariants.t.sol modified.