feat: Add fileupload editor for string arrays to docs (#1979)

Co-authored-by: Michał Olender <[email protected]>

Author: valekjo

sources/platform/actors/development/actor_definition/input_schema/specification.md

@@ -234,6 +234,8 @@ The `anyDate` property renders a date picker that accepts both absolute and rela
 
 The `fileupload` editor enables users to specify a file as input. The input is passed to the Actor as a string. It is the Actor author's responsibility to interpret this string, including validating its existence and format.
 
+The editor makes it easier to users to upload the file to a key-value store of their choice.
+
 ![Apify Actor input schema - fileupload input](./images/input-schema-fileupload-input.png)
 
 The user provides either a URL or uploads the file to a key-value store (existing or new).
@@ -440,7 +442,7 @@ Properties:
 
 | Property | Value | Required | Description |
 | --- | --- | --- | --- |
-| `editor` | One of <ul><li>`json`</li><li>`requestListSources`</li><li>`pseudoUrls`</li><li>`globs`</li><li>`keyValue`</li><li>`stringList`</li><li>`select`</li><li>`hidden`</li></ul> | Yes | UI editor used for input. |
+| `editor` | One of <ul><li>`json`</li><li>`requestListSources`</li><li>`pseudoUrls`</li><li>`globs`</li><li>`keyValue`</li><li>`stringList`</li><li>`fileupload`</li><li>`select`</li><li>`hidden`</li></ul> | Yes | UI editor used for input. |
 | `placeholderKey` | String | No | Placeholder displayed for <br/>key field when no value is specified. <br/>Works only with `keyValue` editor. |
 | `placeholderValue` | String | No | Placeholder displayed in value field <br/>when no value is provided. <br/>Works only with `keyValue` and <br/>`stringList` editors. |
 | `patternKey` | String | No | Regular expression that <br/>will be used to validate <br/>the keys of items in the array. <br/>Works only with `keyValue` <br/>editor. |
@@ -462,6 +464,7 @@ Editor type `requestListSources` supports input in formats defined by the [sourc
 
 Editor type `globs` maps to the Crawlee's [GlobInput](https://crawlee.dev/api/core#GlobInput) used by the [UrlPatterObject](https://crawlee.dev/api/core#UrlPatternObject).
 
+Editor type `fileupload` enables users to specify a list of files as input. The input is passed to the Actor as an array of strings. The Actor author is responsible for interpreting the strings, including validating file existence and format. This editor simplifies the process for users to upload files to a key-value store of their choice.
 Editor type `select` allows the user to pick items from a select, providing multiple choices. Please check this example of how to define the multiselect field:
 
 ```json