add CI

.github/workflows/ci.yml

@@ -0,0 +1,36 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 3.3.0
+
+      - name: Install dependencies
+        run: |
+          gem install bundler
+          bundle install
+
+      - name: Set up database
+        run: bundle exec rails db:create db:migrate
+        env:
+          RAILS_ENV: test
+
+      - name: Run tests
+        run: bundle exec rspec
+        env:
+          RAILS_ENV: test