fix(auth): set SameSite=None for session cookies to fix cross-origin session loss in Tauri apps

internal/auth/cookie.go

@@ -17,7 +17,7 @@ func SetSessionCookie(w http.ResponseWriter, cookieName, token string, duration
 		Path:     "/",
 		HttpOnly: true,
 		Secure:   secure,
-		SameSite: http.SameSiteLaxMode,
+		SameSite: http.SameSiteNoneMode,
 		MaxAge:   int(duration.Seconds()),
 	})
 }

internal/auth/webauthn.go

@@ -234,7 +234,8 @@ func (h *WebAuthnHandler) LoginBegin(w http.ResponseWriter, r *http.Request) {
 		Path:     "/",
 		HttpOnly: true,
 		MaxAge:   300, // 5 minutes
-		SameSite: http.SameSiteStrictMode,
+		SameSite: http.SameSiteNoneMode,
+		Secure:   true,
 	})
 
 	w.Header().Set("Content-Type", "application/json")
@@ -341,7 +342,8 @@ func (h *WebAuthnHandler) LoginFinish(w http.ResponseWriter, r *http.Request) {
 		Path:     "/",
 		HttpOnly: true,
 		MaxAge:   -1,
-		SameSite: http.SameSiteStrictMode,
+		SameSite: http.SameSiteNoneMode,
+		Secure:   true,
 	})
 
 	w.Header().Set("Content-Type", "application/json")