fix: crash on implicit unwrapped optional - WPB-26725

[netbe]

WPB-26725 [iOS] App crashing when tapping on notification from group for inactive account

Issue

• AppLockModule.Interactor.handleAuthenticationResult dispatches its result to the main queue guarding only [weak self], while its presenter property is a weak, implicitly-unwrapped optional (AppLockPresenterInteractorInterface!) that isn't guarded.
• The app-lock module can be torn down and rebuilt mid-flight: AppRootRouter.showAppLock rebuilds a fresh AppLockModule.View/Presenter/Interactor every time the app state re-enters .locked (e.g. when the Face ID/Touch ID/passcode system prompt briefly resigns the app). The old Interactor is kept alive by the pending LocalAuthentication callback closure, but its Presenter (owned only by the now-discarded View) gets deallocated, zeroing the weak presenter reference.
• When the stale callback later fires with .denied, .needCustomPasscode, or .unavailable, the code force-unwraps the nil presenter → EXC_BREAKPOINT / "Unexpectedly found nil while implicitly unwrapping an Optional value" crash (confirmed via crash.log, matches Thread 0 crash + Thread 14's LAContext completion path).

Fix: guard let self, let presenter else { return } in the dispatched closure — mirrors an existing pattern already used elsewhere in the codebase (ImagePickerManager.swift, AudioTrackPlayer.swift, ConversationListViewController+NavigationBar.swift). Stale/orphaned callbacks now no-op instead of crashing.

File changed: Wire-iOS/Sources/UserInterface/App Lock/AppLockModule.Interactor.swift (1 line)

Testing

account A and B are logged in, A is the active account
app is int he background
B receives a notifcation from a group
B tapps on the notification -> app crashes

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Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

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UI accessibility checklist

If your PR includes UI changes, please utilize this checklist:

• Make sure you use the API for UI elements that support large fonts.
• All colors are taken from WireDesign.ColorTheme or constructed using WireDesign.BaseColorPalette.
• New UI elements have Accessibility strings for VoiceOver.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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