chore(#140): add concurrency block to 11 PR workflows (#141)

Adds `concurrency:` with `cancel-in-progress: true` to the 11 GitHub
Actions workflows that previously lacked one. PR-triggered workflows use
`github.event.pull_request.number || github.ref` as the group key;
schedule- and issue-only workflows use `github.ref`.

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

.github/workflows/auto-branch.yml

@@ -4,6 +4,10 @@ on:
   issues:
     types: [labeled]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: write
   issues: write

.github/workflows/auto-label-issues.yml

@@ -4,6 +4,10 @@ on:
   issues:
     types: [opened]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   add-triage-label:
     runs-on: ubuntu-latest

.github/workflows/branch-cleanup.yml

@@ -7,6 +7,10 @@ on:
     - cron: '0 4 * * 0'  # Sunday 4am UTC — weekly orphan sweep
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: write
   pull-requests: read

.github/workflows/branch-naming.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, synchronize]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions: {}
 
 jobs:

.github/workflows/changeset-required.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, synchronize, reopened, labeled, unlabeled]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
   pull-requests: read

.github/workflows/close-draft-prs.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, reopened, converted_to_draft]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   pull-requests: write
 

.github/workflows/docs-required.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, synchronize, reopened, labeled, unlabeled]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
   pull-requests: read

.github/workflows/pr-gate.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, synchronize]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   pull-requests: write
   issues: write

.github/workflows/pr-template-format.yml

@@ -4,6 +4,10 @@ on:
   pull_request_target:
     types: [opened, edited, reopened, synchronize, ready_for_review]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
   issues: write

.github/workflows/require-issue-link.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, edited, reopened, synchronize]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   pull-requests: write
 

.github/workflows/stale.yml

@@ -5,6 +5,10 @@ on:
     - cron: '0 9 * * 1'  # Monday 9am UTC
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   issues: write
   pull-requests: write