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/erasure/README.md

@@ -6,7 +6,7 @@ Silo protects data against hardware failures and silent data corruption using er
 
 Erasure code is a mathematical algorithm to reconstruct missing or corrupted data. Silo uses Reed-Solomon code to shard objects into variable data and parity blocks. For example, in a 12 drive setup, an object can be sharded to a variable number of data and parity blocks across all the drives - ranging from six data and six parity blocks to ten data and two parity blocks.
 
-By default, Silo shards the objects across N/2 data and N/2 parity drives. Though, you can use [storage classes](https://github.com/pgsty/minio/tree/master/docs/erasure/storage-class) to use a custom configuration. We recommend N/2 data and parity blocks, as it ensures the best protection from drive failures.
+By default, Silo shards the objects across N/2 data and N/2 parity drives. Though, you can use [storage classes](https://github.com/pgsty/silo/tree/main/docs/erasure/storage-class) to use a custom configuration. We recommend N/2 data and parity blocks, as it ensures the best protection from drive failures.
 
 In 12 drive example above, with Silo server running in the default configuration, you can lose any of the six drives and still reconstruct the data reliably from the remaining drives.
 
@@ -14,7 +14,7 @@ In 12 drive example above, with Silo server running in the default configuration
 
 Erasure code protects data from multiple drives failure, unlike RAID or replication. For example, RAID6 can protect against two drive failure whereas in Silo erasure code you can lose as many as half of drives and still the data remains safe. Further, Silo's erasure code is at the object level and can heal one object at a time. For RAID, healing can be done only at the volume level which translates into high downtime. As Silo encodes each object individually, it can heal objects incrementally. Storage servers once deployed should not require drive replacement or healing for the lifetime of the server. Silo's erasure coded backend is designed for operational efficiency and takes full advantage of hardware acceleration whenever available.
 
-![Erasure](https://github.com/pgsty/minio/blob/master/docs/screenshots/erasure-code.jpg?raw=true)
+![Erasure](https://github.com/pgsty/silo/blob/main/docs/screenshots/erasure-code.jpg?raw=true)
 
 ## What is Bit Rot protection?
 

docs/erasure/storage-class/README.md

@@ -80,7 +80,7 @@ export MINIO_STORAGE_CLASS_STANDARD=EC:3
 export MINIO_STORAGE_CLASS_RRS=EC:2
 ```
 
-Storage class can also be set via `mc admin config` get/set commands to update the configuration. Refer [storage class](https://github.com/pgsty/minio/tree/master/docs/config#storage-class) for
+Storage class can also be set via `mc admin config` get/set commands to update the configuration. Refer [storage class](https://github.com/pgsty/silo/tree/main/docs/config#storage-class) for
 more details.
 
 #### Note