[BUG] No visible alarm when it goes off

[SLKTH]

Describe the bug

When a timer expires while the app is in the background, no full-screen alarm UI is shown.
The alarm sound plays, but the only way to stop it is by opening the notification or switching back to the app manually.

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To Reproduce

1. Start a timer.
2. Switch to another app.
3. Wait until the timer finishes.
4. The alarm sound plays, but no alarm screen appears automatically.

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Expected behavior

When the timer expires, a full-screen alarm interface should appear so the alarm can be dismissed immediately, even if another app is currently open.

To clarify: I am not referring to a floating timer overlay — only an active alarm screen when it goes off.

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Actual behavior

• Alarm sound plays ✔️
• Notification appears ✔️
• Tapping the notification opens the alarm screen ✔️
• No full-screen alarm UI appears automatically ❌

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Device

• Device model: OnePlus 15
• Android version: Android 16
• App version: v1.8.4
• Installed from: F-Droid (IzzyOnDroid repository)

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Environment details

• Battery usage: Unrestricted (previously Optimized)
• Notifications: Enabled
• No blocked or restricted special permissions found in app settings
• Same behaviour also observed earlier on Samsung S23 (Android 16)

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Additional context

This might be expected behaviour or related to newer Android background restrictions, but I expected a full-screen alarm when the timer expires.
Love using the app nonetheless — thanks for the great work!