Add CI workflow

- Configured GitHub Actions CI to build and compress binaries using UPX.
- Set up workflow to trigger on push and pull requests.

.github/workflows/ci.yml

@@ -0,0 +1,43 @@
+name: CI
+
+on: 
+  pull_request:
+    types: [synchronize, reopened, closed]
+  push:
+    branches: 
+      - main
+
+jobs:
+  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: '1.20'
+
+    - name: Install UPX
+      run: sudo apt-get install -y upx
+
+    - name: Cache Go modules
+      uses: actions/cache@v4
+      with:
+        path: |
+          ~/.cache/go-build
+          ${{ github.workspace }}/go/pkg/mod
+        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+        restore-keys: |
+          ${{ runner.os }}-go-
+
+    - name: Build and compress binaries
+      run: make build
+
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v4
+      with:
+        name: build-artifacts
+        path: build/