chore(assets): regenerate JSON schema

Regenerate oh-my-opencode.schema.json after config export changes

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

assets/oh-my-opencode.schema.json

@@ -82,6 +82,9 @@
     "hashline_edit": {
       "type": "boolean"
     },
+    "model_fallback": {
+      "type": "boolean"
+    },
     "agents": {
       "type": "object",
       "properties": {