Add setting for hiding the status_bar.cursor_position_button (#36288)

Release Notes:

- Added an option for the status_bar.cursor_position_button. Setting to
`false` will hide the button. It defaults to `true`.

This builds off the recent work to hide the language selection button
(https://github.com/zed-industries/zed/pull/33977). I tried to follow
that pattern, and to pick a clear name for the option, but any
feedback/change is welcome.

---------

Co-authored-by: zumbalogy <3770982+zumbalogy@users.noreply.github.com>

assets/settings/default.json

@@ -1256,7 +1256,9 @@
   // Status bar-related settings.
   "status_bar": {
     // Whether to show the active language button in the status bar.
-    "active_language_button": true
+    "active_language_button": true,
+    // Whether to show the cursor position button in the status bar.
+    "cursor_position_button": true
   },
   // Settings specific to the terminal
   "terminal": {