Dashboards: Set limit to default if negative; document functionality (#112659)

docs/sources/developers/http_api/dashboard_versions.md

@@ -24,7 +24,7 @@ title: 'Dashboard Versions HTTP API '
 
 Query parameters:
 
-- **limit** - Maximum number of results to return
+- **limit** - Maximum number of results to return. Defaults to 1000 if not set, or if an invalid value is passed in.
 - **start** - Version to start from when returning queries
 
 `GET /api/dashboards/uid/:uid/versions`

docs/sources/developers/http_api/snapshot.md

@@ -99,7 +99,7 @@ Keys:
 Query parameters:
 
 - **query** – Search Query
-- **limit** – Limit the number of returned results
+- **limit** – Limit the number of returned results. Default is 1000 is not set or provided an invalid value.
 
 **Example Request**: