chore: OSS polish round 3 before going public

[blue4209211]

Summary

Five small fixes before flipping the repo public — all mechanical, no behavior changes.

• README: replace go install github.com/bitnami-labs/kubewatch@latest with a git clone + go build flow. The old command resolved to the upstream repo, not this fork — first-impression bug for anyone trying the local install path.
• docs/CONTRIBUTION.md: delete. Stale older copy of contributing docs that still directed bug reports to bitnami-labs/kubewatch/issues. Canonical guide is the root CONTRIBUTING.md.
• kubewatch-in-cluster.yaml: delete. Byte-identical duplicate of kubewatch.yaml (only the trailing newline differs); README only references the latter.
• .gitignore: add .DS_Store. Two .DS_Store files were sitting untracked in the working tree and would have been committed by accident on the next git add -A.
• Cleaned up the two stray .DS_Store files from the working tree.

Deferred to follow-up PRs (per review):

• Renaming the Go module path from github.com/bitnami-labs/kubewatch to github.com/nudgebee/kubewatch (touches ~20 source files + Dockerfile + Makefile, needs a product call).
• Changing the /opt/bitnami/... config path in the container image.
• RBAC sample, docs/design.md drift, CODEOWNERS expansion, dependabot docker grouping, slackwebhook stray-quote comment.

Tests performed

• Ran git check-ignore .DS_Store pkg/.DS_Store — exits 0 after the gitignore change (was 1 before).
• Confirmed kubewatch-in-cluster.yaml and kubewatch.yaml were byte-identical via diff before deletion.
• Confirmed README.md only references kubewatch.yaml (not kubewatch-in-cluster.yaml) via grep.
• Rendered the updated README install section locally to confirm the code block still formats cleanly.

Notes for reviewers

• No code changes, no Dockerfile changes, no manifest changes beyond the duplicate deletion. CI should be a no-op other than the docs check.

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request updates the .gitignore file to include .DS_Store, replaces the go install instructions in the README.md with a 'Building from source' guide, and removes the CONTRIBUTING.md file and a sample Pod manifest. The reviewer suggested using 'make build' instead of 'go build' in the documentation to ensure that versioning metadata is correctly embedded via the project's Makefile.

[gemini-code-assist]

Using go build directly bypasses the LDFLAGS defined in the Makefile, which are used to embed versioning information (version, git commit, build date) into the binary. It is recommended to use make build to ensure the binary is built with the correct metadata.

Suggested change

	$ go build -o kubewatch
	$ make build