editor: Add setting for snippet sorting behavior for code completion (#29429)

Added `snippet_sort_order`, which determines how snippets are sorted
relative to other completion items. It can have the values `top`,
`bottom`, or `inline`, with `inline` being the default.

This mimics VS Code’s setting:
https://code.visualstudio.com/docs/editing/intellisense#_snippets-in-suggestions

Release Notes:

- Added support for `snippet_sort_order` to control snippet sorting
behavior in code completion menus.

docs/src/configuring-zed.md

@@ -592,7 +592,49 @@ List of `string` values
 
 **Options**
 
-`boolean` values
+1. Never hide the mouse cursor:
+
+```json
+"hide_mouse": "never"
+```
+
+2. Hide only when typing:
+
+```json
+"hide_mouse": "on_typing"
+```
+
+3. Hide on both typing and cursor movement:
+
+```json
+"hide_mouse": "on_typing_and_movement"
+```
+
+## Snippet Sort Order
+
+- Description: Determines how snippets are sorted relative to other completion items.
+- Setting: `snippet_sort_order`
+- Default: `inline`
+
+**Options**
+
+1. Place snippets at the top of the completion list:
+
+```json
+"snippet_sort_order": "top"
+```
+
+2. Place snippets normally without any preference:
+
+```json
+"snippet_sort_order": "inline"
+```
+
+3. Place snippets at the bottom of the completion list:
+
+```json
+"snippet_sort_order": "bottom"
+```
 
 ## Editor Scrollbar