Add GitHub actions CI

Author: Strokkur424

.github/workflows/build.yml

@@ -0,0 +1,36 @@
+name: Java CI
+
+on:
+  push:
+    branches: ["**"]
+  pull_request:
+
+permissions:
+  actions: write
+  contents: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 21
+
+      - name: Grant execute permissions
+        run: chmod +x compile
+
+      - name: Build
+        run: ./compile
+
+      - name: Upload build jar
+        uses: actions/upload-artifact@v4
+        with:
+          name: Build Artifacts
+          path: build/libs/*.jar