feature/1109 grpc session model (#1141)

- **feat: remove Hway deployment**
- **feat: introduce session middleware for requests**
- **refactor: update path imports to use new pkg folder**
- **feat: add gRPC client for interacting with services**
- **feat: remove grpc client and use REST api**
- **refactor: move  from  to**
- **feat: add client views endpoint**
- **feat: add webauthn support**
- **closes: #1124**
- **refactor: Improve PR labeler configuration**
- **feat: add milestone discussion template**
- **feat: remove OKR tracking issue template**
- **feat: use gorilla sessions for session management**
- **refactor: move pubkey related code to**
- **<no value>**
- **refactor: remove unused identifier type**
- **feat: integrate Macaroon Keeper with Service Module**
- **refactor: rename worker routes for clarity**

internal/ctx/authorize.go

@@ -0,0 +1,95 @@
+package ctx
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/labstack/echo/v4"
+	"gopkg.in/macaroon.v2"
+)
+
+const (
+	OriginMacroonCaveat  MacroonCaveat = "origin"
+	ScopesMacroonCaveat  MacroonCaveat = "scopes"
+	SubjectMacroonCaveat MacroonCaveat = "subject"
+	ExpMacroonCaveat     MacroonCaveat = "exp"
+	TokenMacroonCaveat   MacroonCaveat = "token"
+)
+
+var MacroonCaveats = []MacroonCaveat{OriginMacroonCaveat, ScopesMacroonCaveat, SubjectMacroonCaveat, ExpMacroonCaveat, TokenMacroonCaveat}
+
+type MacroonCaveat string
+
+func (c MacroonCaveat) Equal(other string) bool {
+	return string(c) == other
+}
+
+func (c MacroonCaveat) String() string {
+	return string(c)
+}
+
+func (c MacroonCaveat) Verify(value string) error {
+	switch c {
+	case OriginMacroonCaveat:
+		return nil
+	case ScopesMacroonCaveat:
+		return nil
+	case SubjectMacroonCaveat:
+		return nil
+	case ExpMacroonCaveat:
+		// Check if the expiration time is still valid
+		exp, err := time.Parse(time.RFC3339, value)
+		if err != nil {
+			return err
+		}
+		if time.Now().After(exp) {
+			return fmt.Errorf("expired")
+		}
+		return nil
+	case TokenMacroonCaveat:
+		return nil
+	default:
+		return fmt.Errorf("unknown caveat: %s", c)
+	}
+}
+
+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)
+		}
+	}
+}