standardize packaging, tooling, docs, CI, and licensing

.drone.yml

@@ -32,6 +32,26 @@ steps:
           echo "🆕 New version detected: $PACKAGE_NAME==$VERSION"
         fi
 
+  - name: quality-gate
+    image: python:3.13-slim
+    environment:
+      PIP_REPO_URL:
+        from_secret: PIP_REPO_URL
+      PIP_USERNAME:
+        from_secret: PIP_USERNAME
+      PIP_PASSWORD:
+        from_secret: PIP_PASSWORD
+    commands:
+      - pip install --upgrade pip build
+      - |
+        AUTH_URL="https://${PIP_USERNAME}:${PIP_PASSWORD}@$(echo "${PIP_REPO_URL#*://}" | sed 's:/*$::')/simple"
+        pip install --index-url "$AUTH_URL" --extra-index-url https://pypi.org/simple/ -U ".[dev]"
+      - echo "🛡️ Running quality gate..."
+      - python -m black --check .
+      - python -m ruff check .
+      - python -m mypy
+      - python -m pytest
+
   - name: build-package
     image: python:3.13-slim
     commands:
@@ -126,4 +146,4 @@ steps:
 
 trigger:
   event:
-    - custom
+    - custom