Refactor to JSON API with Chi router and interface-based design

- Add pkg/greet/api_v1.go with ApiV1Greet interface and handler
- Implement Greeter interface for dependency injection
- Return JSON responses with proper Content-Type headers
- Move greet service instantiation to server package
- Separate v1 route registration into registerApiV1Routes function
- Health endpoint at /api level, greet endpoints at /api/v1/greet
- Simplify server entrypoint by removing external dependencies

pkg/server/server.go

@@ -0,0 +1,58 @@
+package server
+
+import (
+	"net/http"
+
+	"DanceLessonsCoach/pkg/greet"
+
+	"github.com/go-chi/chi/v5"
+	"github.com/go-chi/chi/v5/middleware"
+)
+
+type Server struct {
+	router *chi.Mux
+}
+
+func NewServer() *Server {
+	s := &Server{
+		router: chi.NewRouter(),
+	}
+	s.setupRoutes()
+	return s
+}
+
+func (s *Server) setupRoutes() {
+	s.router.Use(middleware.Logger)
+	s.router.Route("/api", func(r chi.Router) {
+		r.Use(s.apiMiddlewares()...)
+		r.Get("/health", s.handleHealth)
+		s.registerApiV1Routes(r)
+	})
+}
+
+func (s *Server) registerApiV1Routes(r chi.Router) {
+	r.Route("/v1", func(r chi.Router) {
+
+		greetService := greet.NewService()
+		greetHandler := greet.NewApiV1GreetHandler(greetService)
+		r.Route("/greet", func(r chi.Router) {
+			greetHandler.RegisterRoutes(r)
+		})
+
+	})
+}
+
+func (s *Server) apiMiddlewares() []func(http.Handler) http.Handler {
+	return []func(http.Handler) http.Handler{
+		middleware.StripSlashes,
+		middleware.Recoverer,
+	}
+}
+
+func (s *Server) handleHealth(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte(`{"status":"healthy"}`))
+}
+
+func (s *Server) Router() http.Handler {
+	return s.router
+}