refactor(api): restructured API for type safety, maintainability and docs generation

- These changes makes the API incombatible with previous versions
- Added new types for error handling, success responses, and health checks.
- Updated health check logic to utilize the new types for better clarity and structure.
- Refactored existing handlers to improve response consistency and error handling.
- Updated Makefile to include a new target for generating API types from Swagger.
- Updated "new agent" API to respond an encrypted cert pair

internal/api/v1/homepage/items.go

@@ -0,0 +1,46 @@
+package homepageapi
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apitypes "github.com/yusing/go-proxy/internal/api/types"
+	"github.com/yusing/go-proxy/internal/route/routes"
+)
+
+type HomepageItemsRequest struct {
+	Category string `form:"category" validate:"omitempty"`
+	Provider string `form:"provider" validate:"omitempty"`
+} //	@name	HomepageItemsRequest
+
+// @x-id				"items"
+// @BasePath		/api/v1
+// @Summary		Homepage items
+// @Description	Homepage items
+// @Tags			homepage
+// @Accept			json
+// @Produce		json
+// @Param			category	query		string	false	"Category filter"
+// @Param			provider	query		string	false	"Provider filter"
+// @Success		200			{object}	homepage.Homepage
+// @Failure		400			{object}	apitypes.ErrorResponse
+// @Failure		403			{object}	apitypes.ErrorResponse
+// @Router			/homepage/items [get]
+func Items(c *gin.Context) {
+	var request HomepageItemsRequest
+	if err := c.ShouldBindQuery(&request); err != nil {
+		c.JSON(http.StatusBadRequest, apitypes.Error("invalid request", err))
+		return
+	}
+
+	proto := "http"
+	if c.Request.TLS != nil || c.GetHeader("X-Forwarded-Proto") == "https" {
+		proto = "https"
+	}
+	hostname := c.Request.Host
+	if host := c.GetHeader("X-Forwarded-Host"); host != "" {
+		hostname = host
+	}
+
+	c.JSON(http.StatusOK, routes.HomepageItems(proto, hostname, request.Category, request.Provider))
+}