Add archive notice to README

[timgentry]

This repository is being archived. The GitHub Audit (audit_github) feature has been merged into the main way_of_working gem as a built-in, opt-in feature.

Adds an archive notice just below the README header pointing users to the new home and explaining how to enable the feature there.

🤖 Generated with Claude Code

[github-actions]

🦙 MegaLinter status: ❌ ERROR

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
✅ ACTION	actionlint	3		0	0	0.01s
✅ BASH	bash-exec	1		0	0	0.01s
✅ BASH	shellcheck	1		0	0	0.01s
✅ BASH	shfmt	1		0	0	0.0s
❌ COPYPASTE	jscpd	yes		3	no	1.42s
✅ JSON	jsonlint	1		0	0	0.11s
✅ JSON	v8r	1		0	0	2.49s
⚠️ MARKDOWN	markdownlint	2		1	0	0.98s
❌ MARKDOWN	markdown-link-check	2		1	0	5.05s
✅ MARKDOWN	markdown-table-formatter	2		0	0	0.34s
✅ REPOSITORY	checkov	yes		no	no	17.94s
✅ REPOSITORY	devskim	yes		no	no	1.48s
✅ REPOSITORY	dustilock	yes		no	no	0.02s
✅ REPOSITORY	gitleaks	yes		no	no	0.15s
✅ REPOSITORY	git_diff	yes		no	no	0.01s
❌ REPOSITORY	grype	yes		42	no	42.33s
❌ REPOSITORY	kics	yes		2	no	1.7s
✅ REPOSITORY	secretlint	yes		no	no	0.55s
✅ REPOSITORY	syft	yes		no	no	1.67s
❌ REPOSITORY	trivy	yes		1	no	9.21s
✅ REPOSITORY	trivy-sbom	yes		no	no	1.43s
✅ REPOSITORY	trufflehog	yes		no	no	3.82s
❌ SPELL	lychee	10		4	0	1.26s
✅ YAML	v8r	6		0	0	5.74s
✅ YAML	yamllint	6		0	0	0.43s

See detailed report in MegaLinter reports

You could have the same capabilities but better runtime performances if you use a MegaLinter flavor:

• oxsecurity/megalinter/flavors/terraform@v8.8.0 (55 linters)
• oxsecurity/megalinter/flavors/cupcake@v8.8.0 (88 linters)