Promotes `v5-next` onto `v5` for the **v5.3.0** release.

The head is a single merge commit with parents `v5` (`1d7578e433`) and
`v5-next` (`4aab531902`). Land it with a merge commit, not a squash, so
`v5-next` stays in the ancestry of `v5`.

### Node.js 24.22.1

Included via #25676. `.nvmrc` reads `v24.22.1`, and
`release-image/Dockerfile.base` installs Node 24.22.1 from the
nodejs.org tarball, sha256-checked per architecture, with `apt upgrade`
in the image and `docker build --pull` for the base. Both files are
byte-identical to `v5-next` on this branch.

The CI build image (`build-images/src/Dockerfile`) and
`scripts/setup-container.sh` pin `nodejs=24.15.0-1nodesource1`. The
published `aztecprotocol/aztec` image takes its Node runtime from
`Dockerfile.base`, not from either of those.

### Carried from `v5`

- #25629 (`PROVER_NODE_DISABLE_FULL_EPOCH_PROVING`) is on `v5` only. It
is not on `v5-next`, so no nightly has run it.
- The v5.2.1 cherry-picks (#25616 via #25617, and #25304) are on both
sides and merge without conflict.

### Manifest

`.release-please-manifest.json` is the only conflict: `5.2.1` on `v5`,
`5.3.0` on `v5-next`. It resolves to `5.3.0`.

### Scope

97 commits (56 non-merge), 2026-08-17 to 2026-10-26.

| Area | Changes |
|---|---|
| toolchain | Node.js 24.22.1 (#25676) |
| `aztec-up` | Pin verdaccio 7.0.1 and publish to the local test
registry with a login token (#25690) |
| `aztec-node` | Stop history pruning after a configured checkpoint
(#25656); archive witnesses at the current tip (#25540) |
| `sequencer` | Publisher instance cleanup (#25490); fee provider
refreshes in the background (#25278) |
| `pxe` | Per-change-set staging store and coordinator hardening
(#25335, #25336, #25337, #25338, #25339, #25367); speculative sync of
predicted contract call trees (#25214) |
| `txe` | Immutables hash in TXE deployments (#25541, `feat(txe)!`) |
| `bb` | Reject mixed-infinity recursive accumulators (#25617, also in
v5.2.1) |
| merge trains | `fairies-v5` (#25256, #25329, #25425, #25471, #25483,
#25535, #25539, #25583); `spartan-v5` (#25284, #25325, #25382, #25421) |
| compat | 5.2.0 legacy compat artifact (#25250) |

**One breaking change**: #25541 (`feat(txe)!`).

### Protocol

`v5..v5-next` touches nothing under
`noir-projects/noir-protocol-circuits`, `l1-contracts/src`,
`barretenberg`, `noir` or `yarn-project/constants`.
`pinned-build.tar.gz`, `pinned-protocol-contracts.tar.gz` and
`pinned-standard-contracts.tar.gz` are the same blobs as on `v5`. The
`noir-projects` changes are in `aztec-nr`, `handshake_registry_contract`
(standard, pinned), `schnorr_initializerless_account_contract` and
`tx_effect_oracle_test_contract`.

### Validation

`v5.3.0-nightly.20261022` through `v5.3.0-nightly.20261026` all point at
`31aa3e90f2`, and their CI3 runs are green. The only `v5-next` change
after `31aa3e90f2` is #25690, which touches `aztec-up` CI scripts only.
No v5.3.0 nightly is deployed on testnet:
`v5.testnet.rpc.aztec-labs.com` and
`canonical.testnet.rpc.aztec-labs.com` both report `nodeVersion=5.0.0`.

Not run on this head: the from-source protocol-constants gate, and a
testnet soak.