ci: add Core ecosystem CI workflow with CodeRabbit auto-fix

Uses dAppCore/build actions for test, auto-fix on CodeRabbit changes,
and auto-merge on CodeRabbit approval.

Co-Authored-By: Virgil <virgil@lethean.io>

.github/workflows/ci.yml

@@ -0,0 +1,54 @@
+name: CI
+
+on:
+  push:
+    branches: [main, dev]
+  pull_request:
+    branches: [main]
+  pull_request_review:
+    types: [submitted]
+
+jobs:
+  test:
+    if: github.event_name != 'pull_request_review'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dAppCore/build/actions/build/core@dev
+        with:
+          go-version: "1.26"
+          run-vet: "true"
+
+  auto-fix:
+    if: >
+      github.event_name == 'pull_request_review' &&
+      github.event.review.user.login == 'coderabbitai' &&
+      github.event.review.state == 'changes_requested'
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.ref }}
+          fetch-depth: 0
+      - uses: dAppCore/build/actions/fix@dev
+        with:
+          go-version: "1.26"
+
+  auto-merge:
+    if: >
+      github.event_name == 'pull_request_review' &&
+      github.event.review.user.login == 'coderabbitai' &&
+      github.event.review.state == 'approved'
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - uses: actions/checkout@v4
+      - name: Merge PR
+        run: gh pr merge ${{ github.event.pull_request.number }} --merge --delete-branch
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}