Add .gitattributes file

.gitattributes

@@ -0,0 +1,25 @@
+# Copyright 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.
+
+# Mark files generated by uv to be collapsed by default in PRs.
+# See: https://github.com/github/linguist/#generated-code
+dev_tools/requirements/envs/*.txt linguist-generated=true
+
+# Include Markdown files in GitHub's file statistics for this repo.
+*.md linguist-detectable
+
+# Exclude config files from GitHub's file statistics. Most are YAML files and
+# Linguist already treats .yaml files as data, so only add some exceptions.
+.markdownlintrc linguist-documentation
+.shfmt          linguist-documentation