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 -->

.docker/selfhost/schema.json

@@ -732,6 +732,11 @@
           },
           "default": {}
         },
+        "providers.morph": {
+          "type": "object",
+          "description": "The config for the morph provider.\n@default {}",
+          "default": {}
+        },
         "unsplash": {
           "type": "object",
           "description": "The config for the unsplash key.\n@default {\"key\":\"\"}",