Merge main into feature/testing-framework

Resolved conflicts:
- package.json: Use version 0.1.15 from main
- wp-plugin-starter-template.php: Use version 0.1.15, keep Plugin class usage
- AGENTS.md: Merge both versions, keep CI/CD content
- .wiki/Architecture-Overview.md: Use .agents/ directory structure
- wiki/* files: Delete (moved to .wiki/)
- .agents/error-checking-feedback-loops.md: Keep from feature branch

Also includes:
- Renamed .ai-workflows/ to .agents/
- Renamed .ai-assistant.md to AGENTS.md
- Updated version to 0.1.15

package.json

@@ -1,6 +1,6 @@
 {
   "name": "wp-plugin-starter-template-for-ai-coding",
-  "version": "0.1.13",
+  "version": "0.1.15",
   "description": "A comprehensive starter template for WordPress plugins with best practices for AI-assisted development.",
   "main": "index.js",
   "scripts": {