chore: cut over to pgsty/silo and main

The transitional references land in one commit, because they are only correct
together: the repository is pgsty/silo, its default branch is main, and nothing
in the tree should point a user at the old names.

Changed:

- Workflow branch filters. go.yml and vulncheck.yml gated on `branches: master`
  for both push and pull_request, so renaming the default branch would have
  taken automatic CI offline with no error and no signal - the workflows would
  simply never trigger again. They now name main.
- Release target. goreleaser's `release.github.name` becomes silo, which is
  what actually decides where a tagged build publishes. sign-release-rpms.sh's
  GH_REPO default follows.
- The OCI `image.source` label, the Helm chart `sources` entry, the security
  advisory link in the issue-template config, and the go.mod comment citing the
  LDAP TLS fix.
- 115 occurrences across README, README_ZH, SECURITY, CONTRIBUTING and 30 docs
  pages, including 72 links that also carried the master branch in their path.
  Those matter most: GitHub redirects clone, fetch, push and web URLs after a
  rename, but raw.githubusercontent.com does not, and neither follows a branch
  rename - every one of those links would 404 twice over.
- Three error strings in cmd/erasure-sets.go, cmd/storage-errors.go and
  internal/config/errors.go that print an issue URL to operators. These are Go
  string literals inside rebrand-guard's brand allowlist, so the baseline is
  regenerated. The regeneration removes exactly those three entries and adds
  none; all twelve other protected sets, including the 9014 exported symbols,
  are byte-identical.
- The transitional-naming disclaimers in README, README_ZH, SECURITY and
  CONTRIBUTING are dropped, since they no longer describe anything.

Deliberately unchanged, all three because they exist to reject or freeze the old
name rather than to point at it:

- buildscripts/minio-upgrade.sh pins pgsty/minio@sha256:b6bfe72... - the frozen
  pre-rebrand image is the control group for the MinIO-to-Silo upgrade test.
- helm-migration-guard rejects any rendered container still pulling pgsty/minio.
- verify-rebrand.sh rejects the same in the delivery surfaces.

Also unchanged: docs/config/README.md links to pgsty/mc/blob/master, and that
repository's default branch really is still master. It moves when mc does.

verify-rebrand.sh gains three assertions so this cannot silently regress: no
source reference may name pgsty/minio outside the three allowlisted guards, no
link may target pgsty/silo's master branch, and go.yml and vulncheck.yml must
filter on main. Both new rejections were negative-tested - reintroducing a
master branch filter and adding a pgsty/minio URL each fail the gate with the
specific message.

This commit assumes the rename actually happens. Until the GitHub branch and
repository renames are executed, the links it introduces do not resolve.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/distributed/DESIGN.md

@@ -115,7 +115,7 @@ In above example there are two server pools
 
 > Notice the requirement of common SLA here original cluster had 1024 drives with 16 drives per erasure set with default parity of '4', second pool is expected to have a minimum of 8 drives per erasure set to match the original cluster SLA (parity count) of '4'. '12' drives stripe per erasure set in the second pool satisfies the original pool's parity count.
 
-Refer to the sizing guide with details on the default parity count chosen for different erasure stripe sizes [here](https://github.com/pgsty/minio/blob/master/docs/distributed/SIZING.md)
+Refer to the sizing guide with details on the default parity count chosen for different erasure stripe sizes [here](https://github.com/pgsty/silo/blob/main/docs/distributed/SIZING.md)
 
 Silo places new objects in server pools based on proportionate free space, per pool. Following pseudo code demonstrates this behavior.
 

docs/distributed/README.md

@@ -8,7 +8,7 @@ Silo in distributed mode can help you setup a highly-available storage system wi
 
 ### Data protection
 
-Distributed Silo provides protection against multiple node/drive failures and [bit rot](https://github.com/pgsty/minio/blob/master/docs/erasure/README.md#what-is-bit-rot-protection) using [erasure code](https://silo.pgsty.com/operations/concepts/erasure-coding/). As the minimum drives required for distributed Silo is 2 (same as minimum drives required for erasure coding), erasure code automatically kicks in as you launch distributed Silo.
+Distributed Silo provides protection against multiple node/drive failures and [bit rot](https://github.com/pgsty/silo/blob/main/docs/erasure/README.md#what-is-bit-rot-protection) using [erasure code](https://silo.pgsty.com/operations/concepts/erasure-coding/). As the minimum drives required for distributed Silo is 2 (same as minimum drives required for erasure coding), erasure code automatically kicks in as you launch distributed Silo.
 
 If one or more drives are offline at the start of a PutObject or NewMultipartUpload operation the object will have additional data protection bits added automatically to provide additional safety for these objects.
 
@@ -18,7 +18,7 @@ A stand-alone Silo server would go down if the server hosting the drives goes of
 
 For example, an 16-server distributed setup with 200 drives per node would continue serving files, up to 4 servers can be offline in default configuration i.e around 800 drives down Silo would continue to read and write objects.
 
-Refer to sizing guide for more understanding on default values chosen depending on your erasure stripe size [here](https://github.com/pgsty/minio/blob/master/docs/distributed/SIZING.md). Parity settings can be changed using [storage classes](https://github.com/pgsty/minio/tree/master/docs/erasure/storage-class).
+Refer to sizing guide for more understanding on default values chosen depending on your erasure stripe size [here](https://github.com/pgsty/silo/blob/main/docs/distributed/SIZING.md). Parity settings can be changed using [storage classes](https://github.com/pgsty/silo/tree/main/docs/erasure/storage-class).
 
 ### Consistency Guarantees