Fix flaky ProposeNewConstitution test

[carbolymer]

Summary

• Raise dvtUpdateToConstitution to 51% (from the default 0%) via Conway genesis override, so a minority of yes-votes cannot trigger instant ratification.
• Split voting into two rounds: round 1 (3 yes = 33%, below threshold) keeps the proposal alive for deterministic ledger and CLI assertions; round 2 (+1 yes, +3 no, +2 abstain = 4/7 = 57.1%) crosses the threshold and triggers ratification.
• Replace waitForGovActionVotes + immediate assertions with retryUntilJustM polling that exits only when the exact expected vote count appears in both ledger state and CLI output.
• Extend govActionLifetime to 4 epochs and ratification timeout to epoch 20 so the proposal survives the pulsing snapshot refresh cycle.
• Move query proposals assertion before voting so the proposal structure is verified while it has zero votes (deterministic).

Root cause

The default dvtUpdateToConstitution = 0% means any single DRep yes-vote immediately satisfies the ratification threshold.
Combined with the pulsing snapshot lag (the snapshot only picks up new votes at epoch boundaries), the window where the proposal exists with votes but is not yet ratified is extremely narrow.
The old test submitted all 9 votes at once and then asserted on the transient "proposal with votes" state, which was a race condition.

Approach

Structure the test so that the states we are interested in are longer-lived (addressing review feedback):

1. Override Conway genesis to set a meaningful ratification threshold
2. Vote in rounds so the below-threshold state is stable for assertions
3. Use exact-count polling guards so assertions never fire on stale data

Test plan

• Test passes consistently with DISABLE_RETRIES=1 (4/4 runs, ~75-96s each)
• CI green

[Copilot]

Pull request overview

This PR aims to make the ProposeNewConstitution governance integration test deterministic by avoiding a transient “proposal-with-votes-but-not-yet-ratified” window caused by low (0%) voting thresholds and pulsing snapshot lag.

Changes:

• Overrides Conway genesis in the test to raise dvtUpdateToConstitution (to 51%) and extend govActionLifetime, and updates the configuration.yaml genesis hash accordingly.
• Splits DRep voting into two rounds and replaces “wait then assert” logic with retryUntilJustM polling guards that wait for exact expected vote counts in ledger state and CLI output.
• Updates several golden query outputs (notably PlutusV3 cost model parameter values) and adds .serena/ to .gitignore.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
cardano-testnet/test/cardano-testnet-test/Cardano/Testnet/Test/Gov/ProposeNewConstitution.hs	Reworks the test setup (genesis override + rehash), voting flow (two rounds), and assertion strategy (exact-count polling) to eliminate flakiness.
cardano-testnet/test/cardano-testnet-test/files/golden/queries/protocolParametersOut.txt	Updates expected protocol parameter output (PlutusV3 cost model values).
cardano-testnet/test/cardano-testnet-test/files/golden/queries/protocolParametersFileOut.json	Updates expected protocol parameter JSON output (PlutusV3 cost model values).
cardano-testnet/test/cardano-testnet-test/files/golden/queries/govStateOut.json	Updates expected governance state JSON output (PlutusV3 cost model values).
cardano-testnet/changelog.d/20260629_103800_mgalazyn_fix_flaky_propose_new_constitution.md	Documents the test flake fix and new strategy.
.gitignore	Ignores .serena/ directory.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[palas]

Looks good, just a couple of really minor nits

[palas]

I think this do is redundant, is it for reducing the scope of the inner variables? Same with the do for the second round

[carbolymer]

Yes, it just reduces the scope and makes the test more readable.