Change mjVISSTRING of connect and weld equality constraints from "Constraint" to "Equality". This is more consistent with the 'E' shortcut key and with mjDISABLESTRING ("constraint" means all constraints, "equality" means bilateral constraints).

Also remove unused ampersands from `mjVISSTRING` names, these are a remnant from a very old version of the UI framework.

PiperOrigin-RevId: 593469811
Change-Id: I0f6f73c9f5d2c61b2280f395f76434b0710ce4f3

simulate/simulate.cc

@@ -837,15 +837,8 @@ void MakeRenderingSection(mj::Simulate* sim, const mjModel* m, int oldstate) {
     {mjITEM_END}
   };
   for (int i=0; i<mjNVISFLAG; i++) {
-    // set name, remove "&"
+    // set name
     mju::strcpy_arr(defFlag[0].name, mjVISSTRING[i][0]);
-    for (int j=0; j<strlen(mjVISSTRING[i][0]); j++) {
-      if (mjVISSTRING[i][0][j]=='&') {
-        mju_strncpy(
-          defFlag[0].name+j, mjVISSTRING[i][0]+j+1, mju::sizeof_arr(defFlag[0].name)-j);
-        break;
-      }
-    }
 
     // set shortcut and data
     if (mjVISSTRING[i][2][0]) {
@@ -868,7 +861,10 @@ void MakeRenderingSection(mj::Simulate* sim, const mjModel* m, int oldstate) {
   // add rendering flags
   mjui_add(&sim->ui0, defOpenGL);
   for (int i=0; i<mjNRNDFLAG; i++) {
+    // set name
     mju::strcpy_arr(defFlag[0].name, mjRNDSTRING[i][0]);
+
+    // set shortcut and data
     if (mjRNDSTRING[i][2][0]) {
       mju::sprintf_arr(defFlag[0].other, " %s", mjRNDSTRING[i][2]);
     } else {