Update examples to Aztec v4.3.0

[critesjosh]

Summary

Bumps all examples from Aztec v4.2.0 to v4.3.0.

• Noir deps: aztec-nr tag updated to v4.3.0 across account-contract, custom-note, note-send-proof (circuits, sample-contract, uint-note), prediction-market, recursive_verification/contract.
• JS/TS deps: @aztec/* packages pinned to 4.3.0 in each package.json; lockfiles regenerated.
• CI workflows: AZTEC_VERSION bumped to 4.3.0.
• Docs: READMEs, root CLAUDE.md, and recursive_verification/CLAUDE.md updated for the new version and the rename of bundled nargo to aztec-nargo (the bare nargo is no longer on PATH as of v4.3.0). Nargo version reference updated to 1.0.0-beta.21.
• account-contract:
  • src/main.nr: dropped the now-unneeded get_sender_for_tags / set_sender_for_tags calls in constructor and entrypoint; updated get_low_nullifier_membership_witness to destructure its new (leaf_preimage, witness) return shape.
  • ts/deploy-account-contract.ts: switched to the new DeployMethod.create(wallet, { artifact, postDeployCtor, args, constructorNameOrArtifact }, { salt, universalDeploy, publicKeys }) API; removed the equivalent fields from deployAccountOpts.
• recursive_verification/data.json: regenerated proof data against v4.3.0.

Test plan

• CI: recursive-verification-tests, note-send-proof-tests, prediction-market-tests, test-wallet-webapp-tests all green on the new version.
• Local: aztec-up 4.3.0, then in each example run the documented build/test flow (e.g. yarn ccc && yarn data && yarn test in recursive_verification).
• account-contract: verify deploy via the updated DeployMethod.create API succeeds end-to-end.