docs(mobile-client): clarify location of standard exceptions

- Update description to mention the 'core' shared package
- Add clarification for local repository setup

Author: fulleni

src/content/docs/mobile-client/architecture/error-handling.mdx

@@ -16,7 +16,7 @@ All exceptions that represent business logic or data fetching errors are subtype
 -   `OperationFailedException`: A general-purpose exception for other server-side or unexpected failures.
 
 <Aside>
-You can find the full set of standardized exceptions in the `packages/core/lib/src/exceptions/` directory.
+The full set of standardized exceptions is defined in the `core` shared package. After you have cloned the `core` repository locally, you can find them in its `lib/src/exceptions/` directory.
 </Aside>
 
 ### The Flow of an Exception