Harden dependency automation and remediate Trivy action supply-chain exposure

.github/dependabot.yml

@@ -0,0 +1,29 @@
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "daily"
+      time: "04:00"
+      timezone: "UTC"
+    open-pull-requests-limit: 10
+    rebase-strategy: "auto"
+    groups:
+      production-dependencies:
+        dependency-type: "production"
+        update-types: ["patch", "minor"]
+      development-dependencies:
+        dependency-type: "development"
+        update-types: ["patch", "minor"]
+      major-updates:
+        dependency-type: "production"
+        update-types: ["major"]
+      major-development-updates:
+        dependency-type: "development"
+        update-types: ["major"]
+    labels:
+      - "dependencies"
+      - "dependabot"
+    commit-message:
+      prefix: "chore(deps)"
+      prefix-development: "chore(deps-dev)"

.github/workflows/ci.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
   push:
 
+permissions:
+  contents: read
+  security-events: write
+
 jobs:
   ci:
     runs-on: ubuntu-latest
@@ -21,6 +25,20 @@ jobs:
       - name: Install dependencies
         run: pnpm install --frozen-lockfile
 
+      - name: Dependency Security Scan
+        uses: aquasecurity/trivy-action@57a97c7e7821a5776cebc9bb87c984fa69cba8f1 # v0.35.0
+        with:
+          scan-type: 'fs'
+          ignore-unfixed: true
+          format: 'sarif'
+          output: 'trivy-results.sarif'
+
+      - name: Upload Trivy results
+        if: success() || failure()
+        uses: github/codeql-action/upload-sarif@7fd177fa680c9881b53cdab4d346d32574c9f7f4 # v3
+        with:
+          sarif_file: 'trivy-results.sarif'
+
       - name: Install Foundry
         uses: foundry-rs/foundry-toolchain@v1
         with:

.github/workflows/dependabot-automerge.yml

@@ -0,0 +1,42 @@
+name: Dependabot Auto-Merge & Self-Heal
+
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+permissions:
+  contents: write
+  pull-requests: write
+  checks: read
+
+jobs:
+  dependabot:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    steps:
+      - name: Fetch metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@v2
+        with:
+          github-token: "${{ secrets.GITHUB_TOKEN }}"
+
+      - name: Auto-approve safe updates
+        if: steps.metadata.outputs.update-type == 'version-update:semver-patch' || steps.metadata.outputs.update-type == 'version-update:semver-minor'
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Auto-merge patch & minor
+        if: steps.metadata.outputs.update-type == 'version-update:semver-patch' || steps.metadata.outputs.update-type == 'version-update:semver-minor'
+        run: gh pr merge --auto --squash "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Flag major updates for review
+        if: steps.metadata.outputs.update-type == 'version-update:semver-major'
+        run: gh pr edit "$PR_URL" --add-label "major-update" --add-label "needs-review"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}