fix(e2e): wait for checkpoint in fee_asset_price_oracle_gossip test

[AztecBot]

Summary

Fixes the merge-train/spartan CI failure from Merge branch 'next' into merge-train/spartan (504c330) — the fee_asset_price_oracle_gossip test threw TypeError: Cannot read properties of undefined (reading 'checkpoint') at fee_asset_price_oracle_gossip.test.ts:175.

CI run: https://github.com/AztecProtocol/aztec-packages/actions/runs/24730852209
Failing test log: http://ci.aztec-labs.com/0e05c9015c65aae1

Root cause

The merge brought in #22535 (skip initial sequencer in p2p/epochs tests), which stopped applyBaseSetup from mining an initial block and made setupAccount a PXE-only register (no on-chain tx). Sibling tests gossip_network.test.ts and gossip_network_no_cheat.test.ts were migrated at the same time to submit txs and resolve the checkpoint via getCheckpointedBlock(blockNumber).checkpointNumber, but this spartan-only test was missed and still ran:

const blockNumber = await nodes[0].getBlockNumber();
const [publishedCheckpoint] = await dataStore.getCheckpoints(
  CheckpointNumber.fromBlockNumber(blockNumber),
  1,
);

With no block built yet, blockNumber is 0 and getCheckpoints returns [], so the destructured publishedCheckpoint is undefined.

Fix

Replace the racy one-shot lookup with a retryUntil that waits for (1) a block to be built, (2) that block to be checkpointed, and (3) its checkpoint to be present in the archiver with attestations. Drop the now-unused CheckpointNumber import.

Verification

Ran the single test locally after make yarn-project:

PASS src/e2e_p2p/fee_asset_price_oracle_gossip.test.ts
  e2e_p2p_network
    ✓ should rollup txs from all peers (164105 ms)

Full local ./bootstrap.sh ci was not feasible in the claudebox container (the spartan target needs helm/terraform, neither of which is available locally). Full details: https://gist.github.com/AztecBot/25382b8be3dd7a5a15c90f1c2587a983

Test plan

• merge-queue CI on merge-train/spartan passes for the fee_asset_price_oracle_gossip test

ClaudeBox log: https://claudebox.work/s/495875797419bb4d?run=1

[AztecBot]

Flakey Tests

🤖 says: This CI run detected 2 tests that failed, but were tolerated due to a .test_patterns.yml entry.

\033FLAKED\033 (8;;http://ci.aztec-labs.com/e0e5d6bcc237d82a�e0e5d6bcc237d82a8;;�):  yarn-project/end-to-end/scripts/run_test.sh simple src/e2e_p2p/preferred_gossip_network.test.ts (80s) (code: 0) group:e2e-p2p-epoch-flakes
\033FLAKED\033 (8;;http://ci.aztec-labs.com/031aaee944f13a50�031aaee944f13a508;;�):  yarn-project/end-to-end/scripts/run_test.sh simple src/e2e_p2p/gossip_network.test.ts (212s) (code: 0) group:e2e-p2p-epoch-flakes

[AztecBot]

Automatically closing this stale claudebox draft PR (no updates for 5+ days). Re-open if still needed.