Add PR template and links to contributor guidelines

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,26 @@
+<!--
+Thank you for contributing to an OSGeo Suomi project!
+
+Please write this description yourself. Translation or copy-editing tools are
+fine, pasting LLM output as your design rationale is not. See CONTRIBUTING.md.
+-->
+
+## Summary
+
+<!-- What does this PR do, and why? -->
+
+## Related issues
+
+<!-- e.g. Fixes #123, Refs #456 -->
+
+## How this was tested
+
+<!-- Describe the testing you did, including any manual verification. -->
+
+## Contributor checklist
+
+- [ ] I have read the [CONTRIBUTING guidelines](https://github.com/osgeosuomi/.github/blob/main/CONTRIBUTING.md).
+- [ ] **I have reviewed and understand every change in this pull request, and I take responsibility for it as the author.** This applies whether the changes were written by hand or with the assistance of AI tools.
+- [ ] If AI tools were used to generate a substantial part of this contribution, I have disclosed it in the PR description above or via an `Assisted-by:` commit trailer.
+- [ ] My contribution is licensed under the same license as this repository, and I have the right to submit it.
+- [ ] I have run the project's tests locally where applicable.

README.md

@@ -159,7 +159,9 @@ $ pre-commit install
 
 ## Contributing
 
-Contributions are very welcome.
+Contributions are very welcome. Get started by reading OSGeo
+Suomi [CONTRIBUTING guidelines](https://github.com/osgeosuomi/.github/blob/main/CONTRIBUTING.md).
+
 
 ## License