release: v0.1.7 — editing experience: gutter, auto-format, bracket close, drag-drop, outline

feat(core): line number gutter with current line highlight
- .me-gutter rendered alongside textarea, sync-scrolls with content
- .me-gutter-active highlights the line containing the cursor
- config.lineNumbers (default true) to toggle

feat(core): smart Enter auto-formatting
- List continuation: '- ' / '1. ' auto-insert on Enter at end of list item
- Ordered list auto-increment: '1.' → '2.'
- Quote continuation: '> ' auto-insert on Enter at end of quote line
- Empty list/quote item: Enter removes the marker (end list)

feat(core): bracket/quote auto-close
- (), [], {}, <>, "", '', ``, **, __ auto-close pairs
- Selection wrapping: select text then press ( → wraps as (text)
- config.autoBrackets (default true) to toggle

feat(core): drag & drop file support
- Drop image files → auto base64 inline insert ![](data:...)
- Drop text/code files → insert file contents
- Drop external text from browser → insert at cursor

feat(core): outline/TOC panel
- Extracts headings from rendered HTML preview
- Nested tree with indentation by heading level
- Click to scroll-jump in both preview and textarea
- config.outline (default false) to toggle

style: gutter, outline panel, current line highlight CSS

test: 11 new tests for gutter, auto-format, bracket close, outline (532 total)

chore: bump version 0.1.6 → 0.1.7 across all files, site, types

src/index.js

@@ -1,7 +1,7 @@
 /**
  * MetonaEditor - 轻量级 Markdown Editor 库
  * @module metona-editor
- * @version 0.1.6
+ * @version 0.1.7
  * @author thzxx
  * @description 现代化、零依赖、易扩展、易维护、易使用的 Markdown 编辑器库。单文件，开箱即用。
  * @license MIT
@@ -29,7 +29,7 @@ import { animationUtils } from './animations.js';
 import { DEFAULTS, ICONS, THEMES, EDIT_MODES, DEFAULT_TOOLBAR, TOOLBAR_ACTIONS } from './constants.js';
 
 // 版本信息
-const VERSION = '0.1.6';
+const VERSION = '0.1.7';
 
 /**
  * 全局默认插件队列