feat(backend): add root route with IP info and move swagger to /docs

- Add root route (/) returning JSON with client IP, API info and links
- Move Swagger docs from /swagger/ to /docs/
- Include X-Forwarded-For and X-Real-IP header support for proxy environments

backend/internal/router/router.go

@@ -62,6 +62,33 @@ func NewRouter() http.Handler {
 	jobHandler := handlers.NewJobHandler(jobService)
 	applicationHandler := handlers.NewApplicationHandler(applicationService)
 
+	// --- ROOT ROUTE ---
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/" {
+			http.NotFound(w, r)
+			return
+		}
+		// Get client IP
+		clientIP := r.Header.Get("X-Forwarded-For")
+		if clientIP == "" {
+			clientIP = r.Header.Get("X-Real-IP")
+		}
+		if clientIP == "" {
+			clientIP = r.RemoteAddr
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		response := `{
+	"message": "🐴 GoHorseJobs API is running!",
+	"ip": "` + clientIP + `",
+	"docs": "/docs",
+	"health": "/health",
+	"version": "1.0.0"
+}`
+		w.Write([]byte(response))
+	})
+
 	mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte("OK"))
@@ -106,8 +133,8 @@ func NewRouter() http.Handler {
 		log.Println("S3 storage routes registered successfully")
 	}
 
-	// Swagger Route
-	mux.HandleFunc("/swagger/", httpSwagger.WrapHandler)
+	// Swagger Route - available at /docs
+	mux.HandleFunc("/docs/", httpSwagger.WrapHandler)
 
 	// Apply middleware chain: Security Headers -> Rate Limiting -> CORS -> Router
 	// Order matters: outer middleware runs first