Add code editor for maputnik (#1426)

## Launch Checklist

This PR adds the ability to look at the entire style and edit it in a
code editor that supports syntax highlight, errors, search and more.

- Resolves #820

CC: @Kanahiro as I know you did something similar, probably has better
performance...

After:
<img width="1920" height="937" alt="image"
src="https://github.com/user-attachments/assets/f925cf92-2623-4390-8f75-14d7f6a79171"
/>


 - [x] Briefly describe the changes in this PR.
 - [x] Link to related issues.
- [x] Include before/after visuals or gifs if this PR includes visual
changes.
 - [x] Write tests for all new functionality.
 - [x] Add an entry to `CHANGELOG.md` under the `## main` section.

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Frank Elsinga <frank@elsinga.de>

src/components/CodeEditor.tsx

@@ -0,0 +1,28 @@
+import InputJson from "./InputJson";
+import React from "react";
+import { withTranslation, type WithTranslation } from "react-i18next";
+import { type StyleSpecification } from "maplibre-gl";
+import { type StyleSpecificationWithId } from "../libs/definitions";
+
+export type CodeEditorProps = {
+  value: StyleSpecification;
+  onChange: (value: StyleSpecificationWithId) => void;
+  onClose: () => void;
+} & WithTranslation;
+
+const CodeEditorInternal: React.FC<CodeEditorProps> = (props) => {
+
+  return <>
+    <button className="maputnik-button" onClick={props.onClose} aria-label={props.t("Close")} style={{ position: "sticky", top: "0", zIndex: 1 }}>{props.t("Click to close the editor")}</button>
+    <InputJson
+      lintType="style"
+      value={props.value}
+      onChange={props.onChange}
+      className={"maputnik-code-editor"}
+    />;
+  </>;
+};
+
+const CodeEditor = withTranslation()(CodeEditorInternal);
+
+export default CodeEditor;