Can not load security cookies

## Use case
I implement the sdk for comment system. The system has a auth by social media. The web part put a JWT token into security cookie storage. I need to load the token.

## Proposal
Add `getSecurityCookies()` function

Start by inspecting the plugin's existing WebView and cookie-related entry points on each supported platform; no specific file or test is named in the issue. Determine how the proposed getSecurityCookies function should accept arguments and expose the JWT security cookie, then add coverage for loading it.

Written by the indexing model from the issue text.