Configure pre-commit for license headers and automatic pyink reformat

.pre-commit-config.yaml

@@ -2,6 +2,20 @@
 files: ^(.*\.(py|md|sh|yaml|yml|in|cfg|txt|rst|toml|precommit-toml|wordlist))$
 exclude: ^(\.[^/]*(cache|assets|uv|venv)/.*)$
 repos:
+  - repo: https://github.com/Lucas-C/pre-commit-hooks
+    rev: v1.5.5
+    hooks:
+      - id: insert-license
+        name: Add license for all Python files
+        files: \.py$|\.bzl$|BUILD$|BUILD\.bazel$
+        args:
+          - --comment-style
+          - "|#|"
+          - --license-filepath
+          - LICENSE_HEADER
+          - --use-current-year
+          - --allow-past-years
+
   - repo: https://github.com/codespell-project/codespell
     rev: v2.4.1
     hooks:
@@ -52,7 +66,6 @@ repos:
         args:
           - '--pyink-indentation=2'
           - '--line-length=122'
-          - '--check'
 
   - repo: https://github.com/executablebooks/mdformat
     rev: 0.7.22

LICENSE_HEADER

@@ -0,0 +1,13 @@
+ Copyright 2023–2026 Google LLC
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.