fix(ns_http): corrected optional id parsing in ns_http list/stats

 - Use Ns_ObjvString instead of Ns_ObjvObj for the optional ?id
   argument in HttpListObjCmd() and HttpStatsObjCmd().

 - Ensure that "ns_http list ?id?" and "ns_http stats ?id?" accept a
   plain string ID again, matching the documented Tcl interface.

Bug is present only in NaviServer 5.0.0–5.0.3; release/4.99 is not affected.
Credit: identified and fixed by Zoran Vasiljevic.

Author: gustafn

nsd/tclhttp.c

@@ -2257,7 +2257,7 @@ HttpListObjCmd(
     char          *idString = NULL;
     int            result = TCL_OK;
     Ns_ObjvSpec    args[] = {
-        {"?id", Ns_ObjvObj, &idString, NULL},
+        {"?id", Ns_ObjvString, &idString, NULL},
         {NULL, NULL, NULL, NULL}
     };
 
@@ -2380,7 +2380,7 @@ HttpStatsObjCmd(
     char          *idString = NULL;
     int            result = TCL_OK;
     Ns_ObjvSpec    args[] = {
-        {"?id", Ns_ObjvObj, &idString, NULL},
+        {"?id", Ns_ObjvString, &idString, NULL},
         {NULL, NULL, NULL, NULL}
     };