feat: aztecnr log prefixing (#22027) [v4-next backport]

[AztecBot]

Summary

Backport of #22027 to v4-next.

Routes aztec-nr logs through a separate aztecnr: prefix channel (vs user contract: logs), enabling pino log filters to separate them. Also adds a comment explaining why the length parameter exists in the uti_log oracle.

Cherry-pick conflicts

Only yarn-project/aztec/scripts/aztec.sh had conflicts — the next branch has a compile step before the TXE start that doesn't exist on v4-next. Resolution: kept v4-next base (no compile step) while applying the log filter rename from contract_log to contract.

Commits

1. Cherry-pick with conflicts — raw cherry-pick of 52a0af8 with conflict markers in aztec.sh
2. Conflict resolution — resolved aztec.sh conflict (kept v4-next structure, applied log filter rename)
3. Second cherry-pick — clean cherry-pick of 3b25b93 (revert parameter renames to preserve oracle interface hash)

ClaudeBox log: https://claudebox.work/s/9576800105ece815?run=1

[AztecBot]

Flakey Tests

🤖 says: This CI run detected 3 tests that failed, but were tolerated due to a .test_patterns.yml entry.

\033FLAKED\033 (8;;http://ci.aztec-labs.com/b67f5236ccee6aa4�b67f5236ccee6aa48;;�):  yarn-project/end-to-end/scripts/run_test.sh simple src/e2e_epochs/epochs_mbps.parallel.test.ts "deploys a contract and calls it in separate blocks within a slot" (180s) (code: 0) group:e2e-p2p-epoch-flakes
\033FLAKED\033 (8;;http://ci.aztec-labs.com/3f39393ed409bdac�3f39393ed409bdac8;;�):  yarn-project/end-to-end/scripts/run_test.sh simple src/e2e_epochs/epochs_mbps.parallel.test.ts "builds multiple blocks per slot with transactions anchored to checkpointed block" (177s) (code: 0) group:e2e-p2p-epoch-flakes
\033FLAKED\033 (8;;http://ci.aztec-labs.com/906c632f04a2295a�906c632f04a2295a8;;�):  yarn-project/end-to-end/scripts/run_test.sh simple src/e2e_epochs/epochs_proof_fails.parallel.test.ts "does not allow submitting proof after epoch end" (243s) (code: 0) group:e2e-p2p-epoch-flakes