Remove AJV schemas

We were keeping those around for a transition period while we moved to
vscode-json-languageservice. This transition period is over.

We can remove those things now.

Author: charlespwd

package.json

@@ -12,7 +12,6 @@
     "test": "vitest"
   },
   "devDependencies": {
-    "ajv": "^8.12.0",
     "lodash.set": "^4.3.2",
     "prettier": "^2.8.8",
     "vitest": "^0.32.2",