docs: add contributing

.github/pull_request_template.md

@@ -0,0 +1,14 @@
+## Check List
+
+<!-- Please check the list. Please don't remove the check list. -->
+
+- [ ] Read [CONTRIBUTING.md](https://github.com/aquaproj/aqua/blob/main/CONTRIBUTING.md)
+  - [ ] Read [OSS Contribution Guide](https://github.com/suzuki-shunsuke/oss-contribution-guide/blob/main/README.md)
+- [ ] [Write a GitHub Issue before creating a Pull Request](https://github.com/suzuki-shunsuke/oss-contribution-guide/blob/main/README.md#create-an-issue-before-creating-a-pull-request)
+  - Link to the issue:
+- [ ] [All commits are signed](https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits)
+  - This repository enables `Require signed commits`, so all commits must be signed
+- [ ] [Avoid force push](https://github.com/suzuki-shunsuke/oss-contribution-guide?tab=readme-ov-file#dont-do-force-pushes-after-opening-pull-requests)
+- [ ] Do only one thing in one Pull Request
+
+<!-- Please write the description here -->

CONTRIBUTING.md

@@ -0,0 +1,6 @@
+# Contributing
+
+Please read the following document.
+
+- https://github.com/suzuki-shunsuke/oss-contribution-guide
+- https://github.com/suzuki-shunsuke/oss-contribution-guide/blob/main/docs/commit-signing.md

README.md

@@ -1,11 +1,9 @@
 # devcontainer-features
 
+[MIT](LICENSE) | [Contributing](CONTRIBUTING.md)
+
 [Development Container Features](https://containers.dev/implementors/features/) for [aqua](https://aquaproj.github.io/)
 
 ## Features
 
 - [aqua-installer](src/aqua-installer): Feature to install aqua
-
-## LICENSE
-
-[MIT](LICENSE)