[ZacLou]

Summary

Closes #176

Problem

governance::approve() required signers to approve in strictly increasing signer-index order. If a higher-index signer approved before a lower-index one, every signer with a lower index became permanently unable to approve — even if quorum could still be met. In the worst case, the highest-index signer could unilaterally and permanently deadlock any proposal (threshold >= 2) just by approving first.

Root cause

if !proposal.approved_by.is_empty() {
    let last_signer = proposal.approved_by.get(proposal.approved_by.len() - 1).unwrap();
    let last_index = signer_index(env, &last_signer);
    let current_index = signer_index(env, signer);
    if current_index <= last_index { panic_with_error!(env, GovError::InvalidSignerOrder); }
}

Fix

Removed the signer ordering constraint (10 lines). The existing proposal.approved_by.contains(signer) check on line 206 already prevents double-approval. Any signer who hasn't yet approved can now approve at any time, in any order, until threshold is reached.

Impact

• Security improvement: prevents permanent governance deadlock
• No new dependencies or attack surface — the double-approval guard remains in place
• Backward compatible: existing valid approval sequences continue to work unchanged

[ZacLou]

Closing this to keep the queue tidy.