chore(repo): add codeowners and basic ci

.github/CODEOWNERS

@@ -0,0 +1,9 @@
+* @phamnazage-jpg
+
+.github/ @phamnazage-jpg
+db/ @phamnazage-jpg
+docs/ @phamnazage-jpg
+internal/ @phamnazage-jpg
+prd/ @phamnazage-jpg
+scripts/ @phamnazage-jpg
+test/ @phamnazage-jpg

.github/workflows/ci.yml

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+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  verify:
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+          cache: true
+
+      - name: Verify formatting
+        run: |
+          gofmt -w $(find . -name '*.go' -not -path './vendor/*')
+          git diff --exit-code
+
+      - name: Run unit and integration tests
+        run: go test ./... -count=1
+
+      - name: Run race tests
+        run: go test -race ./...
+
+      - name: Run vet
+        run: go vet ./...
+
+      - name: Check Gate scripts syntax
+        run: |
+          bash -n scripts/verify_preprod_gate_b.sh
+          bash -n scripts/verify_gate_c_rollback.sh