dev: use doomemacs/ci@legacy

And add common triage workflow.

Author: hlissner

.github/workflows/add-to-project.yml

@@ -1,17 +1,7 @@
 name: Add issues to project
-
 on:
   issues:
-    types:
-      - opened
-
+    types: [opened]
 jobs:
   add-to-project:
-    name: Add issue to project
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/add-to-project@main
-        with:
-          project-url: https://github.com/orgs/doomemacs/projects/2
-          github-token: ${{ github.token }}
-          labeled: needs-triage
+    uses: doomemacs/ci/.github/workflows/add-to-project.yml@legacy

.github/workflows/triage.yml

@@ -0,0 +1,7 @@
+name: Mark stale issues and lock closed threads
+on:
+  schedule:
+    - cron: '0 */12 * * *'  # twice, daily
+jobs:
+  triage:
+    use: doomemacs/ci/.github/workflows/triage.yml@legacy