DEP-268: doc: switch local kind guide to RustFS - #39125

Follow-up to #39125
([DEP-268](https://linear.app/materializeinc/issue/DEP-268)).

**Issue:**
- Released versions of persist cannot read multipart blobs from RustFS,
because RustFS omits `x-amz-mp-parts-count`. #39115 fixes this, but no
release has it yet. Following the current local kind guide on v26.42.0,
any batch part over 8 MiB crashes environmentd or crash-loops a cluster
with `Invalid Parquet file. Corrupt footer`.
- `misc/helm-charts/testing/minio.yaml` pulls `quay.io/minio/minio`,
which no longer allows anonymous pulls, so the orchestratord nightly
workflows cannot start MinIO.

**Solution:**
- `testing/minio.yaml` runs `materialize/minio:v26.42.0`, our own MinIO
build, which is published under every release tag. The image has no
`mc`, so a Job creates the buckets instead of the postStart hook. The
service name, credentials, and buckets are unchanged, so the
`persist_backend_url` in released `materialize.yaml` files keeps
working.
- The guide fetches `minio.yaml` from `main` and no longer asks users to
edit `persist_backend_url`.
- `workflow_documentation_defaults` follows the guide again.

**Gotchas:**
- `rustfs.yaml` stays in `misc/helm-charts/testing` for the RustFS move
once a release contains #39115.
- The orchestratord workflows run only in Nightly, so they need a
Nightly trigger on this PR.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <[email protected]>

The v26.44.0 release-note train, one commit per snapshot. Dates in RC
snapshots are provisional until the release ships; the final snapshot
sets the real dates.

**rc.1** adds the `## v26.44.0` section — 6 Improvements, 3 Agent
Skills, 4 Bug Fixes — and the `v26.44` row in the self-managed operator
compatibility table. No Features section: nothing in this snapshot's 144
in-scope PRs rises to one. The Agent Skills section is back after five
empty windows — the window `(2026-09-23T16:49:13Z,
2026-09-25T02:18:32Z]` holds 4 PRs and all 4 are published.

**final** sets the real dates and adds no new bullets. Nothing shipped
on the materialize side between `v26.44.0-rc.1` and the `v26.44.0` tag:
`GET /compare/v26.44.0-rc.1...v26.44.0` is `ahead_by: 1`, and that one
commit is the version bump, so every `rc.1` classification and all four
verified flag defaults still hold at the ship tag. This train has only
one RC (no `v26.44.0-rc.2` tag exists). Its two changes are:

- **Real dates**: Cloud **2026-09-30**, Self-Managed **2026-10-01**,
from the `v26.44.0` tag's commit date (`2026-09-30T10:50:59Z`) and `+1
day` — one day earlier than the provisional pair rc.1 carried, exactly
as rc.1 predicted. Both date lines in `_index.md` and the `Release
date:` in the YAML are updated.
- **One cross-snapshot rewrite, not a new bullet**:
[agent-skills#74](MaterializeInc/agent-skills#74)
finishes the `mz-` rename that
[#68](MaterializeInc/agent-skills#68) left
`materialize-docs` out of. Rather than publishing a second Agent Skills
bullet saying skills were renamed to `mz-`, `materialize-docs` is now
`mz-docs` is folded into the existing **`mz-` skill names** bullet as
another example. The rc.1 snapshot directory is left as the record of
what was reviewed at the time.

The final commit preserves the two Features a human editor added to this
branch — **SCIM group-to-role mapping is generally available** and
**Operational dashboards for Self-Managed** — and leaves the
Improvements and Bug Fixes sections untouched.

⚠️ **Reviewer checks**

- **The hedged-reads entry has an open testing caveat — still open, and
the one entry to cut if it stays open.** #39110 flips
`persist_blob_hedged_get_enabled` to `true` in the code default, which
is what carries the capability to Self-Managed — Cloud has served it on
through LaunchDarkly since 2026-09-24. But the PR states that real GCS
and Azure object stores are not yet tested (CI covers MinIO and Azurite)
and that testing under
[PER-120](https://linear.app/materializeinc/issue/PER-120) "should
finish before this reaches self-managed users." Nothing in the `final`
increment resolves this, and Linear was not reachable from that run.
**If [PER-120](https://linear.app/materializeinc/issue/PER-120) has not
closed, cut this entry before merging.** It is the only conditional
entry in the release.
- **The balancerd connection-limit entry changes the meaning of
something already published.** `balancerd_max_connections` shipped an
entry in v26.42.0 rc.2 describing over-limit connections as "rejected
with an error". #38854 removes that: the `TOO_MANY_CONNECTIONS` response
and the HTTPS 503 are gone, and a client over the limit now sees libpq's
"server closed the connection unexpectedly". Anyone who built alerting
on the v26.42.0 wording needs this.
- **Two PRs are excluded as already published by the v26.43.0 train** —
#38615 and #39029. Both merged to `main` inside the rc.1 window and were
cherry-picked onto the v26.43 release branch, where that train's rc.2
snapshot published them. Accounted for in `omitted.md` under "Already
published in an earlier release".
- **This branch will need a rebase if the v26.43.0 docs PR merges
first.** `_index.md` here still jumps from `## v26.44.0` to `##
v26.42.0` — the v26.43.0 section is absent because that train's PR
([#38928](#38928)) has
not merged. Whichever of the two merges second needs the rebase to get
the sections in version order.
- **Resolved:** rc.1's provisional dates were flagged as very likely one
day high. They were — the `final` snapshot corrects them down by one
day, on the tag date.

**Inclusion rate is 9.7% (14/144) at rc.1**, inside the usual 5–15%
band, and **20% (1/5) at `final`**, which reads high only because the
denominator is five. The rc.1 denominator is dominated by dependency
automation — 91 of the 142 materialize PRs are dependency bumps, 65 of
them a single Dependabot fan-out of the
`materialize-terraform-self-managed` modules across five
`test/terraform` directories. Strip those and the materialize side is 10
included out of 49.

Snapshot drafts (with PR links) in mz-skills:
- rc.1:
[release_notes.md](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/rc.1/release_notes.md)
/
[omitted.md](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/rc.1/omitted.md)
- final:
[release_notes.md](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/final/release_notes.md)
/
[omitted.md](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/final/omitted.md)

**Borderline PRs omitted:** rc.1: 7 — [review borderline
calls](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/rc.1/omitted.md#borderline),
final: 0 —
[none](https://github.com/MaterializeInc/mz-skills/blob/main/data/mz-release-notes/v26.44.0/final/omitted.md#borderline).

The rc.1 borderline calls are unchanged by seeing the whole release,
since `final` adds no materialize PRs. Two are still worth a reviewer's
eye: #39125 (the local kind install guide moving to RustFS) — the
documented Self-Managed local-kind install **fails today** for every
published tag, because their `minio.yaml` references a Docker Hub
repository MinIO deleted, and this is the likeliest restoration; and
#39034/#39066 (the catalog half of the Console cluster-utilization
memory and swap columns) — **if that Console PR shipped in this release,
it belongs in the notes as a Console improvement.** Three further items
are gated on flags (`enable_upsert_v2`,
`enable_compute_index_peek_offload`, `enable_unified_cluster`).

---------

Co-authored-by: Claude <[email protected]>
Co-authored-by: Valerie Chiang <[email protected]>
Co-authored-by: Pranshu Maheshwari <[email protected]>
Co-authored-by: Pranshu Maheshwari <[email protected]>