Refresh Kubernetes catalog and contributor guide

Author: rootsongjc

CONTRIBUTING.md

@@ -1,15 +1,30 @@
-## Contribution Guidelines
+# Contribution Guidelines
 
-- **To add, remove, or change things on the list:** Submit a pull request
-- List items should be sorted *alphabetically*.
-- Each item should be limited to one link.
-- The link should be the name of the package or project.
-- The project should be hosted on GitHub.
-- Descriptions should be clear, concise, and non-promotional.
-- Descriptions should follow the link, on the same line and end with a punctuation mark.
+Thanks for helping keep this Kubernetes and cloud-native catalog sharp. Please follow the rules below so the list stays consistent and searchable.
+
+## General expectations
+
+- Additions **must be open source** (ideally GitHub-hosted) and clearly benefit cloud-native workloads.
+- Place each project in the **single best matching top-level category** from the table of contents. If unsure, explain the rationale in the PR description.
+- Keep descriptions on a single line, start with sentence case, and avoid marketing fluff.
+- Use the official project name as the link text and point directly to the canonical repository.
+
+## Ordering & formatting
+
+- Categories and items are maintained in **alphabetical order**. Run `go test ./...` (see below) before submitting; it will fail if ordering or duplicates are wrong.
+- One entry per project. Remove retired or duplicate links when encountered.
+- New entries go directly under the relevant `##` heading with a trailing period only if the sentence is complete.
+
+## Local checks before PR
+
+1. `gofmt -w repo.go repo_test.go` (only needed if you touched Go files).
+2. `go test ./...` – verifies alphabetical ordering and ensures no duplicate links.
+3. `go run ./repo.go` – regenerates `tmpl/index.html`; run this whenever README content changes so the published site stays in sync.
+
+Include the commands you ran in your pull request description.
 
 ## Reporting issues
 
-Please open an issue if you would like to discuss anything that could be improved or have suggestions for making the list a more valuable resource. We realize sometimes packages fall into abandonment or have breaking builds for extended periods of time, so if you see that, feel free to change its listing or let us know. We also realize that sometimes projects are just going through transitions or are more experimental in nature. These can still be cool, but we can indicate them as transitory or experimental.
+Open an issue when you find outdated, broken, or abandoned projects, or when you’d like to propose a new category. Provide links or context so maintainers can validate quickly.
 
-Thank you for your contribution!
+Thanks again for contributing!