test(e2e): add 4-node 4-disk distributed Actions suite

Add a nightly e2e-distributed lane that boots localhost 4-node clusters
and covers S3, object lock, versioning, replication, quota, expand,
decommission, rebalance, site replication, concurrency, and chaos.

Co-authored-by: RustFS <hello@rustfs.com>

docs/testing/distributed-e2e.md

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+# Distributed 4-node 4-disk e2e
+
+**Use this when:** adding or diagnosing GitHub Actions coverage for a 4-node cluster, or deciding whether a behaviour belongs in `e2e-distributed` versus the single-node `e2e-full` lane, the nightly cluster-fault lane, or the hardware functional chain.
+**Source of truth:** `crates/e2e_test/src/distributed/`, `[profile.e2e-distributed]` in `.config/nextest.toml`, `.github/workflows/e2e-distributed.yml`.
+
+## Topology
+
+The in-tree harness runs every node on `127.0.0.1` with a distinct port. That matches `RustFSTestClusterEnvironment` in `crates/e2e_test/src/common.rs`:
+
+| Layout | Constructor | Use |
+|---|---|---|
+| 4 nodes × 4 drives, one pool | `ClusterTopology::single_pool_multidrive(4, 4)` | S3, object lock, versioning, quota, observability, concurrency, chaos |
+| 4 nodes × 1 drive, one pool | `ClusterTopology::single_pool(4)` | Two-site replication (8 processes total) |
+| 4 single-node pools × 4 drives | `ClusterTopology::per_node_pools(4, [[0],[1],[2],[3]])` | Decommission, rebalance, S3-during-move, integrity |
+| 2 single-node pools × 4 drives, then `append_single_node_pool` | expansion seed | Pool expand then rebalance |
+
+A pool striped across several localhost ports is not expressible (`RUSTFS_VOLUMES` host ellipses would collide on disk paths). Multi-host striped pools remain the hardware functional-chain / backlog #1313 / #1314 lane.
+
+## What this lane covers
+
+`cargo nextest run --profile e2e-distributed -p e2e_test` selects `distributed::*`:
+
+- S3 put / get / head / list / copy / rename / delete / presign / empty object
+- Object Lock COMPLIANCE, GOVERNANCE (with bypass), legal hold
+- Versioning, version GET, delete marker
+- Bucket replication between two 4-node clusters; hard quota
+- Health / admin info / storageinfo / audit target list
+- Pool expand, decommission, rebalance, checksum integrity, S3 during move
+- Site replication object convergence
+- High-concurrency PUT/GET; concurrent PUT during decommission
+- Node kill/restart, full process restart, drive offline, volume-proxy blackhole
+- Multipart and cross-node listing agreement
+
+## Existing Actions gaps this lane does not replace
+
+Those suites stay in place; this lane fills the in-tree 4×4 hole they leave.
+
+| Existing lane | Gap |
+|---|---|
+| `rustfs-*-test.yml` functional chain | Clones private `rustfs/auto-testing`, runs on three shared VMs (`vm000`–`vm002`), `continue-on-error: true`, not a merge signal, not 4 nodes |
+| `e2e-smoke` / `e2e-full` | Almost all cases are single-node |
+| `e2e-nightly` | 4-node cluster faults and heal, not S3/lock/versioning/quota/decommission matrix |
+| `e2e-repl-nightly` | Site and bucket replication on 1–3 *single-node* processes |
+| `e2e-s3tests.yml` `multi` | Weekly ceph/s3-tests against Docker 4-node; not lock/WORM, decommission, chaos, or checksum integrity |
+| `crates/e2e_test/src/chaos.rs` | Single-node disk faults only |
+
+Hardware power-loss, NIC pull, and real disk replacement still belong on the smoke-testing VMs. This lane simulates those with SIGKILL, directory rename, and `FaultProxy` blackhole.
+
+## Run
+
+```bash
+cargo build -p rustfs --bins
+cargo nextest run --profile e2e-distributed -p e2e_test
+```
+
+Membership is pinned by `.config/e2e-distributed-selection.txt`. Update it with `python3 ./scripts/check_test_wiring.py --update-profile e2e-distributed <listing.json> linux` after adding or renaming a case.