fix: correct TOC indentation to use 2 spaces per level instead of 4

## CHANGES

- Fix indentation calculation for TOC subsections
- Change from 4-space to 2-space indentation
- Update indent formula to `level - 1`
- Bump version from 1.3.2 to 1.4.0

Author: ksylvan

bin/md-tree.js

@@ -715,7 +715,7 @@ For more information, visit: https://github.com/ksylvan/markdown-tree-parser
         }
       } else if (heading.level > 2 && currentLevel2Filename) {
         // This is a subsection within a level 2 section
-        const indent = '    '.repeat(heading.level - 2);
+        const indent = '  '.repeat(heading.level - 1);
         const anchor = this.createAnchor(heading.text);
         toc += `${indent}- [${heading.text}](./${currentLevel2Filename}#${anchor})\n`;
       }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@kayvan/markdown-tree-parser",
-  "version": "1.3.2",
+  "version": "1.4.0",
   "description": "A powerful JavaScript library and CLI tool for parsing and manipulating markdown files as tree structures using the remark/unified ecosystem",
   "type": "module",
   "main": "index.js",