feat: introduce archify skill for generating architecture diagrams

- Added a new Archify skill, enabling users to create polished architecture, workflow, sequence, data-flow, and lifecycle diagrams.
- Implemented comprehensive functionality including rendering, validation, and delivery of diagrams in various formats.
- Integrated a user-friendly command-line interface for generating and previewing diagrams.
- Developed supporting files including package.json, LICENSE, and SKILL.md for documentation and licensing.
- Added unit tests to ensure reliability and functionality of the new skill.

These changes enhance the application by providing a structured approach to visualizing system architecture and workflows, improving user experience and data representation.

.agents/skills/archify/test/site-language-integration.mjs

@@ -0,0 +1,9 @@
+process.env.ARCHIFY_SITE_INTEGRATION = '1';
+
+// GitHub-hosted Linux runners require the same explicit Chrome sandbox opt-out
+// already used by this workflow's other real-browser regression steps.
+if (process.platform === 'linux' && process.env.GITHUB_ACTIONS === 'true') {
+  process.env.ARCHIFY_CHROME_NO_SANDBOX = '1';
+}
+
+await import('./site-language-continuity.test.mjs');