feature/dwn sw js (#1103)

- **feat(macaroon): add  and  to macaroon genesis**
- **refactor: move schema definitions to dedicated file**
- **feat: remove Session model**
- **refactor: move session middleware to internal package**

internal/auth/middleware.go

@@ -0,0 +1,48 @@
+package auth
+
+import (
+	"net/http"
+
+	"github.com/labstack/echo/v4"
+	"gopkg.in/macaroon.v2"
+)
+
+func MacaroonMiddleware(secretKeyStr string, location string) echo.MiddlewareFunc {
+	secretKey := []byte(secretKeyStr)
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			// Extract the macaroon from the Authorization header
+			auth := c.Request().Header.Get("Authorization")
+			if auth == "" {
+				return c.JSON(http.StatusUnauthorized, map[string]string{"error": "Missing Authorization header"})
+			}
+
+			// Decode the macaroon
+			mac, err := macaroon.Base64Decode([]byte(auth))
+			if err != nil {
+				return c.JSON(http.StatusBadRequest, map[string]string{"error": "Invalid macaroon encoding"})
+			}
+
+			token, err := macaroon.New(secretKey, mac, location, macaroon.LatestVersion)
+			if err != nil {
+				return c.JSON(http.StatusBadRequest, map[string]string{"error": "Invalid macaroon"})
+			}
+
+			// Verify the macaroon
+			err = token.Verify(secretKey, func(caveat string) error {
+				for _, c := range MacroonCaveats {
+					if c.String() == caveat {
+						return nil
+					}
+				}
+				return nil // Return nil if the caveat is valid
+			}, nil)
+			if err != nil {
+				return c.JSON(http.StatusUnauthorized, map[string]string{"error": "Invalid macaroon"})
+			}
+
+			// Macaroon is valid, proceed to the next handler
+			return next(c)
+		}
+	}
+}