fix(js): coerce non-string primitives in before/after/replaceWith

before(), after() and replaceWith() only converted string arguments to Text
nodes; other primitives (numbers, booleans, null) were passed straight to
insert_before with no _nid, corrupting the call. Route them through the shared
_convertNodes helper (the same path append/prepend use), so every non-node
argument becomes document.createTextNode(String(n)).

Fixes #498

crates/obscura-js/js/bootstrap.js

@@ -4122,13 +4122,13 @@ if (typeof Response === 'undefined') {
 }
 
 if (!Element.prototype.replaceWith) {
+  // _convertNodes turns any non-node argument (numbers, booleans, null, …) into
+  // a Text node via String(n), matching the spec and append()/prepend(); the
+  // old `typeof n === 'string'` check corrupted insert_before for other types.
   Element.prototype.replaceWith = function(...nodes) {
     const parent = this.parentNode;
     if (!parent) return;
-    for (const n of nodes) {
-      if (typeof n === 'string') parent.insertBefore(document.createTextNode(n), this);
-      else parent.insertBefore(n, this);
-    }
+    for (const n of _convertNodes(nodes)) parent.insertBefore(n, this);
     parent.removeChild(this);
   };
   _markNative(Element.prototype.replaceWith);
@@ -4137,10 +4137,7 @@ if (!Element.prototype.before) {
   Element.prototype.before = function(...nodes) {
     const parent = this.parentNode;
     if (!parent) return;
-    for (const n of nodes) {
-      if (typeof n === 'string') parent.insertBefore(document.createTextNode(n), this);
-      else parent.insertBefore(n, this);
-    }
+    for (const n of _convertNodes(nodes)) parent.insertBefore(n, this);
   };
   _markNative(Element.prototype.before);
 }
@@ -4149,10 +4146,7 @@ if (!Element.prototype.after) {
     const parent = this.parentNode;
     if (!parent) return;
     const ref = this.nextSibling;
-    for (const n of nodes) {
-      if (typeof n === 'string') parent.insertBefore(document.createTextNode(n), ref);
-      else parent.insertBefore(n, ref);
-    }
+    for (const n of _convertNodes(nodes)) parent.insertBefore(n, ref);
   };
   _markNative(Element.prototype.after);
 }