Fix accepting a certificate crashing ICSx5

[sunkup]

Purpose

Accepting a certificate crashes ICSx5.

Short description

• update cert4android
• track foreground state and pass to cert4android (same way as in DAVx5)

Checklist

• The PR has a proper title, description and label.
• I have self-reviewed the PR.
• I have added documentation to complex functions and functions that can be used by other modules.
• I have added reasonable tests or consciously decided to not add tests.

[Copilot]

Pull Request Overview

This PR fixes a crash in ICSx5 that occurs when accepting a certificate by updating the cert4android library and implementing proper foreground state tracking.

• Updates cert4android library to version 41009d4 which likely contains the fix for the certificate acceptance crash
• Implements a ForegroundTracker singleton to track when the app is in the foreground/background
• Integrates the foreground tracking with cert4android's CustomCertManager to enable proper certificate dialog handling

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
gradle/libs.versions.toml	Updates cert4android library version from f0964cb to 41009d4
app/src/main/java/at/bitfire/icsdroid/ui/ForegroundTracker.kt	Adds new singleton class to track app foreground/background state using StateFlow
app/src/main/java/at/bitfire/icsdroid/ui/theme/Theme.kt	Integrates foreground tracking into the app theme using LifecycleResumeEffect
app/src/main/java/at/bitfire/icsdroid/AppHttpClient.kt	Updates CustomCertManager to use the ForegroundTracker instead of a hardcoded false value

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[ArnyminerZ]

Feel free to merge