feat: update input schema docs (#1081)

Updates the docs to include the new `prefill` property on Boolean fields
in the input schema. When the field has a `default` value set now, we
display the `default` chip, to differentiate between them and
regular/prefilled fields.

Related to https://github.com/apify/apify-core/pull/16390/

Also, polite request - please merge this when the above PR is out - I
won't be able to since I won't be at Apify anymore :)

Author: m-murasovs

sources/platform/actors/development/actor_definition/input_schema/images/input-schema-options.png

@@ -203,12 +203,6 @@ When using escape characters `\` for the regular expression in the `pattern` fie
 
 ### Boolean
 
-:::caution `prefill` limitation
-
-Beware that the `boolean` input type doesn't support the `prefill` property since there is no way to display the pre-filled value in the user interface.
-
-:::
-
 Example options with group caption:
 
 ```json5
@@ -226,7 +220,7 @@ Example options with group caption:
         "type": "boolean",
         "description": "If checked then actors runs at the
             speed of light.",
-        "default": true
+        "prefill": true
     }
 }
 ```