Simplify exports and fix variable declarations

Cleanup UMD bundle output: remove intermediate `var _default` and assign `._exports.default` directly in both loader and rtrace builds; move `TOTAL_OVERHEAD` assignment onto `_exports` (remove redundant `const`) in rtrace; fix indentation/initialization of the `off` variable in the loader string-decoding loop. Minor formatting and cleanup across the two UMD files.

Author: BlobMaster41

lib/loader/umd/index.js

@@ -92,7 +92,7 @@
       return utf16.decode(wtf16);
     } catch {
       let str = "",
-        off = 0;
+          off = 0;
       while (len - off > STRING_CHUNKSIZE) {
         str += String.fromCharCode(...wtf16.subarray(off, off += STRING_CHUNKSIZE));
       }
@@ -468,7 +468,7 @@
     }
     return extendedExports;
   }
-  var _default = _exports.default = {
+  _exports.default = {
     instantiate,
     instantiateSync,
     instantiateStreaming,

lib/rtrace/umd/index.js

@@ -38,7 +38,7 @@
   const PTR_VIEW = Uint32Array;
   const BLOCK_OVERHEAD = _exports.BLOCK_OVERHEAD = PTR_SIZE;
   const OBJECT_OVERHEAD = _exports.OBJECT_OVERHEAD = 16;
-  const TOTAL_OVERHEAD = _exports.TOTAL_OVERHEAD = BLOCK_OVERHEAD + OBJECT_OVERHEAD;
+  _exports.TOTAL_OVERHEAD = BLOCK_OVERHEAD + OBJECT_OVERHEAD;
   function assert(x) {
     if (!x) throw Error("assertion failed");
     return x;
@@ -340,7 +340,7 @@
     }
   }
   _exports.Rtrace = Rtrace;
-  var _default = _exports.default = {
+  _exports.default = {
     Rtrace
   };
 });