FDN-02/FDN-03/FDN-07/FDN-08: Migrations-Rollback, Objekt-Storage-Interface, go.sum-Fix, Observability

- FDN-02: Rollback-fähige Down-Migrationen (024-026), archivdms seed dev CLI
- FDN-03: internal/objectstore Interface + lokaler WORM-Treiber, signierte Download-URLs
- FDN-07: go.mod/go.sum vervollständigt (fehlender go-ldap/v3-Eintrag), CI-Pipeline (.gitea/workflows/ci.yml, bereits in FDN-01 committet) damit lauffähig
- FDN-08: Request-ID-Middleware, /metrics-Endpoint, Panic-Recovery, Login/Logout/Me technisches Logging inkl. Access-Log je Anfrage

internal/api/dashboard_handlers.go

@@ -21,7 +21,7 @@ func (s *Server) handleDashboard(w http.ResponseWriter, r *http.Request) {
 
 	stats, err := s.store.GetDashboardStats(r.Context(), *sess.TenantID, sess.UserID)
 	if err != nil {
-		s.logger.Error("dashboard stats failed", "err", err)
+		s.reqLog(r.Context()).Error("dashboard stats failed", "err", err)
 		writeError(w, http.StatusInternalServerError, "dashboard stats failed")
 		return
 	}