ci: add github actions workflow and fix readme badge

- Create .github/workflows/ci.yml with test and build steps
- Fix CI badge link in README.md to point to the new workflow

Author: ESousa97

.github/workflows/ci.yml

@@ -0,0 +1,36 @@
+name: CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  test:
+    name: Test and Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.25.x'
+          cache: true
+
+      - name: Install dependencies
+        run: go mod download
+
+      - name: Verify dependencies
+        run: go mod verify
+
+      - name: Run vet
+        run: go vet ./...
+
+      - name: Run tests
+        run: go test -v -race -coverprofile=coverage.txt -covermode=atomic ./...
+
+      - name: Build
+        run: go build -v -o toolkit ./cmd/toolkit