Initial commit: Developer Tools MVP with visual editor

- Complete React app with 7 developer tools
- JSON Tool with visual structured editor
- Serialize Tool with visual structured editor
- URL, Base64, CSV/JSON, Beautifier, Diff tools
- Responsive navigation with dropdown menu
- Dark/light mode toggle
- Mobile-responsive design with sticky header
- All tools working with copy/paste functionality

node_modules/webpack-sources/lib/helpers/splitIntoLines.js

@@ -0,0 +1,33 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+
+"use strict";
+
+/**
+ * @param {string} str string
+ * @returns {string[]} array of string separated by lines
+ */
+const splitIntoLines = (str) => {
+	const results = [];
+	const len = str.length;
+	let i = 0;
+	while (i < len) {
+		const cc = str.charCodeAt(i);
+		// 10 is "\n".charCodeAt(0)
+		if (cc === 10) {
+			results.push("\n");
+			i++;
+		} else {
+			let j = i + 1;
+			// 10 is "\n".charCodeAt(0)
+			while (j < len && str.charCodeAt(j) !== 10) j++;
+			results.push(str.slice(i, j + 1));
+			i = j + 1;
+		}
+	}
+	return results;
+};
+
+module.exports = splitIntoLines;