feat: add test workflow and implement unit tests for main functionality

.gitea/workflows/test-application.yaml

@@ -0,0 +1,39 @@
+name: Test Application
+run-name: ${{ gitea.actor }} tests the application
+on:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v5
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.12"
+
+      - name: Create and activate virtual environment
+        run: |
+          python -m venv venv
+          source venv/bin/activate
+          pip install -r requirements.txt
+          pip install pytest
+
+      - name: Run tests
+        run: |
+          source venv/bin/activate
+          pytest --maxfail=1 --disable-warnings -q
+
+      - name: Deactivate virtual environment
+        run: deactivate
+
+      - name: Clean up virtual environment
+        run: rm -rf venv