[517] Add checkOnResume to stop the version check on app resume

[tologonkudaiberdiuulu]

Fixes #517.

Problem

Upgrader registers itself as a WidgetsBindingObserver during initialize(), and didChangeAppLifecycleState unconditionally called updateVersionInfo() on every AppLifecycleState.resumed event. That means a network request to the App Store / Play Store every time the app returns from the background, with no way to turn it off.

As noted in the issue, this is unrelated to durationUntilAlertAgain, which only controls how often the alert is displayed, not how often the version info is retrieved. The two are now decoupled.

Change

Added a checkOnResume parameter to Upgrader, defaulting to true, so existing behavior is unchanged. When false, the version info is only retrieved during initialize(), or when updateVersionInfo() is called directly.

Upgrader(checkOnResume: false)

The parameter is stored in UpgraderState, so it can also be changed at runtime:

upgrader.updateState(upgrader.state.copyWith(checkOnResume: false));

The observer is still registered in both cases; only the version check is skipped, and a debug log line is printed when debugLogging is enabled.

Tests

Two tests were added using a request counting MockClient:

• default behavior still retrieves version info on resume
• with checkOnResume: false, repeated resume/pause cycles make no additional requests, while the version info from initialize() remains available and shouldDisplayUpgrade() still returns true

flutter analyze is clean and all tests pass.

[larryaasen]

Thanks for this PR. It has been approved and released on pub.dev