feat(server): add morph doc edit tool (#12789)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **New Features**
- Introduced support for the Morph provider in the copilot module,
enabling integration with the Morph LLM API.
- Added a new document editing tool that allows users to propose and
apply edits to existing documents via AI assistance.
- **Configuration**
- Added configuration options for the Morph provider in both backend and
admin interfaces.
- **Enhancements**
- Expanded tool support to include document editing capabilities within
the copilot feature set.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/admin/src/config.json

@@ -253,6 +253,10 @@
       "type": "Object",
       "desc": "The config for the anthropic provider in Google Vertex AI."
     },
+    "providers.morph": {
+      "type": "Object",
+      "desc": "The config for the morph provider."
+    },
     "unsplash": {
       "type": "Object",
       "desc": "The config for the unsplash key."