fix: Include the loader's Class.wrap in generated TS definitions (#1618)

Author: forcepusher

NOTICE

@@ -29,6 +29,7 @@ under the licensing terms detailed in LICENSE:
 * Valeria Viana Gusmao <[email protected]>
 * Gabor Greif <[email protected]>
 * Martin Fredriksson <[email protected]>
+* forcepusher <[email protected]>
 
 Portions of this software are derived from third-party works licensed under
 the following terms:

src/definitions.ts

@@ -496,6 +496,12 @@ export class TSDBuilder extends ExportsWalker {
       sb.push(extendsNode.name.identifier.text); // TODO: fqn?
     }
     sb.push(" {\n");
+    if (!isInterface) {
+      indent(sb, this.indentLevel);
+      sb.push("static wrap(ptr: usize): ");
+      sb.push(name);
+      sb.push(";\n");
+    }
     var staticMembers = element.prototype.members;
     if (staticMembers) {
       // TODO: for (let member of staticMembers.values()) {