[Enhancement] Show Follow Requests in GUI

[Leaced]

Problem

The current UI does not indicate whether the Follow button represents a follow‑request or an immediate follow.

• When a user clicks Follow on an account that requires approval, the button remains in its original state and no notification is shown.
• There is no way to tell if a follow request is already pending for that account.

This makes it hard for users to understand the status of their follow actions.

Expected behavior

The button should clearly reflect the current state:

• “Request Follow” when the target account requires approval.
• “Revoke Follow Request” (or similar) when a request is already pending.

After clicking, the UI should update instantly to show the new state and optionally display a brief confirmation toast (e.g., “Follow request sent”).