feat: expose ChiRouter method for plugin compatibility

Plugins need access to the underlying chi.Router for route registration.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

modules/web/router.go

@@ -52,6 +52,11 @@ func NewRouter() *Router {
 	return &Router{chiRouter: r}
 }
 
+// ChiRouter returns the underlying chi.Router for plugin compatibility
+func (r *Router) ChiRouter() chi.Router {
+	return r.chiRouter
+}
+
 // Use supports two middlewares
 func (r *Router) Use(middlewares ...any) {
 	for _, m := range middlewares {