Add confirmation dialog when ending an active activity #517

What happens
When an activity is running, tapping Finish immediately ends the session. This can happen by accident if the user taps the button unintentionally, causing the activity to stop without warning.

What I expected instead
I expected the app to show a confirmation dialog asking the user if they are sure they want to end the activity, preventing accidental termination.

Why this matters
Accidentally ending an activity can interrupt tracking, produce incomplete data, and negatively affect the user experience. A confirmation step would avoid unintended interruptions and make the activity flow more reliable.

Suggested improvement
When the user taps Finish, display a confirmation message such as:
“Are you sure you want to end this activity?”
with options like Cancel and End Activity.

Steps to reproduce

Start any activity (Walking, Running, Cycling, etc.).

Tap Finish.

The activity ends immediately without any confirmation.

If tapped by mistake, the session is lost.

Strap log
The strap log behaves normally, but since the activity ends instantly, any accidental termination results in incomplete data.