Add nativeccd flag. When this flag is enabled, general convex collision detection is handled natively, as opposed to using libccd.

PiperOrigin-RevId: 663859009
Change-Id: Ife18bb1de62f2154e4725fdf764484a18586b836

src/xml/xml_native_reader.cc

@@ -116,10 +116,10 @@ const char* MJCF[nMJCF][mjXATTRNUM] = {
         "solver", "iterations", "ls_iterations", "noslip_iterations", "mpr_iterations",
         "sdf_iterations", "sdf_initpoints", "actuatorgroupdisable"},
     {"<"},
-        {"flag", "?", "22", "constraint", "equality", "frictionloss", "limit", "contact",
+        {"flag", "?", "23", "constraint", "equality", "frictionloss", "limit", "contact",
             "passive", "gravity", "clampctrl", "warmstart",
             "filterparent", "actuation", "refsafe", "sensor", "midphase", "eulerdamp", "autoreset",
-            "override", "energy", "fwdinv", "invdiscrete", "multiccd", "island"},
+            "override", "energy", "fwdinv", "invdiscrete", "multiccd", "island", "nativeccd"},
     {">"},
 
     {"size", "*", "14", "memory", "njmax", "nconmax", "nstack", "nuserdata", "nkey",
@@ -1137,6 +1137,7 @@ void mjXReader::Option(XMLElement* section, mjOption* opt) {
     READENBL("invdiscrete", mjENBL_INVDISCRETE)
     READENBL("multiccd",    mjENBL_MULTICCD)
     READENBL("island",      mjENBL_ISLAND)
+    READENBL("nativeccd",   mjENBL_NATIVECCD)
 #undef READENBL
   }
 }