Add pre-commit, fix trailing whitespace

.pre-commit-config.yaml

@@ -0,0 +1,25 @@
+repos:
+  - repo: https://github.com/pycqa/flake8
+    rev: 7.3.0
+    hooks:
+      - id: flake8
+        args: ["--select=F"]
+        types: [python]
+
+  - repo: https://github.com/psf/black-pre-commit-mirror
+    rev: 25.11.0
+    hooks:
+      - id: black
+        language_version: python3
+
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.4.0
+    hooks:
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+
+  - repo: https://github.com/PyCQA/bandit
+    rev: 1.9.2
+    hooks:
+    - id: bandit
+      files: ^src/jinjaturtle/