Use a `schema` (singular) folder like the `style` folder. Use the plugin IDs for the schema file names.

packages/codemirror-extension/package.json

@@ -33,7 +33,7 @@
   "jupyterlab": {
     "extension": true,
     "schemas": [
-      "schemas/jupyter.services.codemirror-services.json"
+      "schema/jupyter.services.codemirror-commands.json"
     ]
   },
   "repository": {

packages/fileeditor-extension/package.json

@@ -30,7 +30,10 @@
     "watch": "tsc -w"
   },
   "jupyterlab": {
-    "extension": true
+    "extension": true,
+    "schemas": [
+      "schema/jupyter.services.editor-tracker.json"
+    ]
   },
   "repository": {
     "type": "git",

packages/fileeditor-extension/schema/jupyter.services.editor-tracker.json

@@ -0,0 +1,21 @@
+{
+  "jupyter.lab.setting-icon-class": "jp-ImageTextEditor",
+  "jupyter.lab.setting-icon-label": "Editor",
+  "title": "Text Editor",
+  "description": "Text editor settings for all editors.",
+  "properties": {
+    "autoClosingBrackets": {
+      "type": "boolean", "title": "Autoclosing Brackets", "default": true
+    },
+    "lineNumbers": {
+      "type": "boolean", "title": "Line Numbers", "default": true
+    },
+    "lineWrap": {
+      "type": "boolean", "title": "Line Wrap", "default": false
+    },
+    "matchBrackets": {
+      "type": "boolean", "title": "Match Brackets", "default": true
+    }
+  },
+  "type": "object"
+}