feat: Implement Swagger documentation and integrate Gin framework for API

backend/cmd/api/main.go

@@ -3,14 +3,36 @@ package main
 import (
 	"fmt"
 	"net/http"
+
+	"github.com/gin-gonic/gin"
+	swaggerFiles "github.com/swaggo/files"
+	ginSwagger "github.com/swaggo/gin-swagger"
+
+	_ "github.com/timetracker/backend/docs" // This line is important for swag to work
 )
 
-func helloHandler(w http.ResponseWriter, r *http.Request) {
-	fmt.Fprintln(w, "Hello from the Time Tracker Backend!")
+// @title Time Tracker API
+// @version 1.0
+// @description This is a simple time tracker API.
+// @host localhost:8080
+// @BasePath /
+
+// @Summary Say hello
+// @Description Get a hello message
+// @ID hello
+// @Produce  plain
+// @Success 200 {string} string "Hello from the Time Tracker Backend!"
+// @Router / [get]
+func helloHandler(c *gin.Context) {
+	c.String(http.StatusOK, "Hello from the Time Tracker Backend!")
 }
 
 func main() {
-	http.HandleFunc("/", helloHandler)
+	r := gin.Default()
+
+	r.GET("/", helloHandler)
+	r.GET("/swagger/*any", ginSwagger.WrapHandler(swaggerFiles.Handler))
+
 	fmt.Println("Server listening on port 8080")
-	http.ListenAndServe(":8080", nil)
+	r.Run(":8080") // Use Gin's Run method
 }