maintenance!: lock old and outdated issues

To avoid spamming dead issues from years ago with unhelpful comments
Locks all closed issues more than 180 days old
This allows recently closed issues to be reopened if necessary

.github/workflows/lock.yml

@@ -0,0 +1,25 @@
+name: 'Lock old issues'
+
+on:
+  schedule:
+    - cron: '*/30 * * * *'
+  workflow_dispatch:
+
+permissions:
+  issues: write
+  pull-requests: write
+
+concurrency:
+  group: lock
+
+jobs:
+  action:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: dessant/lock-threads@v4
+        with:
+          github-token: ${{ github.token }}
+          issue-inactive-days: '180'
+          issue-lock-reason: 'resolved'
+          process-only: 'issues'
+          log-output: false