fix(jsx/dom): handle empty arrays in render children loop (#4729)

* fix(jsx/dom): handle empty arrays in render children loop

When an empty array is spliced into the children list, the loop index
still increments, causing the next child to be skipped. This leads to
a TypeError when accessing properties of undefined nodes.

Add i-- and continue after splice so the loop re-examines the same
index after flattening, correctly handling empty arrays.

* ci: apply automated fixes

---------

Co-authored-by: Maks Pikov <mixelburg@users.noreply.github.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: mixelburg

src/jsx/dom/index.test.tsx

@@ -119,6 +119,24 @@ describe('DOM', () => {
     expect(root.innerHTML).toBe('Hello')
   })
 
+  it('render with empty array followed by non-empty array', () => {
+    const tags: string[] = []
+    const terms: string[] = ['hello']
+    const App = () => (
+      <div>
+        {tags.map((x) => (
+          <span>{x}</span>
+        ))}
+        {terms.map((x) => (
+          <span>{x}</span>
+        ))}
+        <input type='text' />
+      </div>
+    )
+    render(<App />, root)
+    expect(root.innerHTML).toBe('<div><span>hello</span><input type="text"></div>')
+  })
+
   describe('performance', () => {
     it('should be O(N) for each additional element', () => {
       const App = () => (

src/jsx/dom/render.ts

@@ -487,6 +487,8 @@ export const build = (context: Context, node: NodeObject, children?: Child[]): v
     for (let i = 0; i < children.length; i++) {
       if (Array.isArray(children[i])) {
         children.splice(i, 1, ...(children[i] as Child[]).flat())
+        i--
+        continue
       }
       let child = buildNode(children[i])
       if (child) {