merge: stack widget modernization on dnd kit

apps/docs/docs/management/api/index.mdx

@@ -1,9 +1,12 @@
 ---
+
 title: API
 tags:
-  - API
-  - Development
-  - Interface
+
+- API
+- Development
+- Interface
+
 ---
 
 Using the Homarr API, you can interface with the application with your own code and business logic.
@@ -90,3 +93,23 @@ Multi-integration widget queries keep data from integrations that remain availab
 an optional `error` on a failed integration; media-request responses expose a `failedIntegrations` array, and the latest
 requests endpoint returns its items in `requests`. When every selected integration fails, the query returns an error instead
 of a partial response.
+
+### Saving dashboard layouts
+
+The dashboard editor saves item positions and sections as one board update.
+Canvas height follows its content automatically and does not require a separate API setting.
+Responsive layouts store optional left and right gutter widths from zero to three columns.
+Gutter columns are reserved from the layout's total column count, and changing them reflows affected items.
+
+## Get Custom Widget authoring resources
+
+Custom JSX v2 provides four HTTP discovery endpoints:
+
+- `GET /api/custom-widgets/authoring-prompt` returns the current prompt plus MCP and HTTP resource identifiers.
+- `GET /api/custom-widgets/schema` returns the canonical widget JSON Schema.
+- `GET /api/custom-widgets/components` returns the release-matched static component catalog.
+- `GET /api/custom-widgets/skill` returns the concise live `SKILL.md` plus skills.sh, source, and install metadata. Retrieve the schema, component catalog, and examples through their dedicated resources only when needed.
+
+Call `customWidget_configurationRequestUser` to create a temporary API source setup URL where the user can confirm their server URL and enter credentials. Do not construct or save this URL.
+
+Authenticated tRPC and MCP procedures support definition management, validation, previews, template patches, and credential writes. An exported definition does not contain credentials.