feat: Code Mode Button Position & Markdown Support! 📝

## ✅ 3. Code Mode Button Moved to Left
**Problem:** Inconsistent layout, tabs on right should be Editor/Preview only
**Solution:**
- Moved Code Mode button next to "Message Body" label
- Editor/Preview tabs stay on the right
- Consistent, logical layout

**Before:**
```
Message Body                [Editor|Preview] [Code Mode]
```

**After:**
```
Message Body [Code Mode]                [Editor|Preview]
```

## ✅ 4. Markdown Support in Code Mode! 🎉
**Problem:** HTML is verbose, not user-friendly for tech-savvy users
**Solution:**
- Added Markdown parser with ::: syntax for cards
- Toggle between HTML and Markdown modes
- Full bidirectional conversion

**Markdown Syntax:**
```markdown
:::card
# Heading
Your content here
:::

:::card[success]
✅ Success message
:::

[button](https://example.com){Click Here}
[button style="outline"](url){Secondary Button}
```

**Features:**
- Standard Markdown: headings, bold, italic, lists, links
- Card blocks: :::card or :::card[type]
- Button blocks: [button](url){text}
- Variables: {order_url}, {customer_name}
- Bidirectional conversion (HTML ↔ Markdown)

**Files:**
- `lib/markdown-parser.ts` - Parser implementation
- `components/ui/code-editor.tsx` - Mode toggle
- `routes/Settings/Notifications/EditTemplate.tsx` - Enable support
- `DEPENDENCIES.md` - Add @codemirror/lang-markdown

**Note:** Requires `npm install @codemirror/lang-markdown`

Ready for remaining improvements (5-6)!

admin-spa/DEPENDENCIES.md

@@ -6,7 +6,7 @@ Install all dependencies at once:
 
 ```bash
 cd admin-spa
-npm install @tiptap/extension-text-align @tiptap/extension-image codemirror @codemirror/lang-html @codemirror/theme-one-dark @radix-ui/react-radio-group
+npm install @tiptap/extension-text-align @tiptap/extension-image codemirror @codemirror/lang-html @codemirror/lang-markdown @codemirror/theme-one-dark @radix-ui/react-radio-group
 ```
 
 ---
@@ -24,12 +24,13 @@ npm install @tiptap/extension-text-align @tiptap/extension-image
 
 ### CodeMirror (for Code Mode)
 ```bash
-npm install codemirror @codemirror/lang-html @codemirror/theme-one-dark
+npm install codemirror @codemirror/lang-html @codemirror/lang-markdown @codemirror/theme-one-dark
 ```
 
 **What they do:**
 - **codemirror**: Core editor with professional features
 - **@codemirror/lang-html**: HTML syntax highlighting & auto-completion
+- **@codemirror/lang-markdown**: Markdown syntax highlighting & auto-completion
 - **@codemirror/theme-one-dark**: Professional dark theme
 
 ### Radix UI (for UI Components)