Fix clash:// deep link not opening app due to premature Activity finish

[xiwangly2]

Problem

When opening a clash://install-config?url=... deep link, the app would flash briefly or appear to not open at all.

Root Cause

In ExternalControlActivity.onCreate(), the ACTION_VIEW branch launches an async coroutine to create the profile and then start PropertiesActivity. However, after the when block, there is an unconditional return finish() at the end of onCreate(). Since launch {} returns immediately, the Activity was being destroyed before the coroutine completed — causing startActivity() to be called on an already-finished Activity.

Fix

Added a return statement after the launch {} block in the ACTION_VIEW branch to prevent execution from falling through to the premature finish(). The coroutine now manages the Activity lifecycle itself, calling finish() after startActivity() succeeds.

[AlexFozor]

I was actually running into this exact same issue.

Whenever I clicked a deep link, it looked like nothing happened. But if I clicked it multiple times and opened the app manually later, I was suddenly hit with a bunch of stacked "Profile" dialogs all at once.

This PR should fix the problem. Could we get this merged?