ci: add dependabot configuration with auto-merge

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: jgeluk

.github/dependabot.yml

@@ -0,0 +1,36 @@
+version: 2
+updates:
+  - package-ecosystem: "pip"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "sunday"
+      time: "22:00"
+      timezone: "UTC"
+    groups:
+      all-dependencies:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "build(deps)"
+      include: "scope"
+    labels:
+      - "dependencies"
+      - "python"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "sunday"
+      time: "22:00"
+      timezone: "UTC"
+    groups:
+      all-dependencies:
+        patterns:
+          - "*"
+    commit-message:
+      prefix: "ci"
+      include: "scope"
+    labels:
+      - "dependencies"
+      - "github-actions"

.github/workflows/dependabot-approve.yml

@@ -0,0 +1,18 @@
+name: Auto-approve Dependabot
+
+on: pull_request_target
+
+permissions:
+  pull-requests: write
+
+jobs:
+  approve:
+    runs-on: ubuntu-latest
+    if: github.actor == 'dependabot[bot]'
+    steps:
+      - name: Approve Dependabot PR
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+

.github/workflows/dependabot-automerge.yml

@@ -0,0 +1,19 @@
+name: Dependabot auto-merge
+
+on: pull_request
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  automerge:
+    runs-on: ubuntu-latest
+    if: github.actor == 'dependabot[bot]'
+    steps:
+      - name: Enable auto-merge for Dependabot PRs
+        run: gh pr merge --auto --rebase "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+