chore: [SDK-4194] add no-location Flutter demo

[fadi-george]

Description

One Line Summary

Adds a minimal Flutter demo-no-location app stacked on the SDK-4194 location-module opt-out work.

iOS:

default	17:26:48.076411-0700	SpringBoard	RX com.onesignal.example(26079) focusApplicationWithPID:26079 stealKeyboard:Y
    context:<contextID:2107512835 sceneID:com.onesignal.example-default>
default	17:26:48.076081-0700	Runner	TX focusApplication (peekAppEvent) stealKB:Y scene:com.onesignal.example-default
default	17:26:48.775547-0700	Runner	TX focusApplication (peekAppEvent) stealKB:Y scene:com.onesignal.example-default
default	17:26:48.775859-0700	SpringBoard	RX com.onesignal.example(26079) focusApplicationWithPID:26079 stealKeyboard:Y
    context:<contextID:2107512835 sceneID:com.onesignal.example-default>
default	17:26:48.846646-0700	Runner	ERROR: OneSignalLocation not found. In order to use OneSignal's location features the OneSignalLocation module must be added.
default	17:26:48.849788-0700	Runner	flutter: OneSignal.Location.requestPermission did not throw.

Android:

I/ImeTracker(28779): com.onesignal.example:4a60fd82: onCancelled at PHASE_CLIENT_ALREADY_HIDDEN
D/OneSignal(28779): [OneSignalFlutterBg] LocationManager.requestPermission()
W/OneSignal(28779): [OneSignalFlutterBg] Requesting location permission, but location sharing must also be enabledby setting isShared to true
I/OneSignal(28779): [OneSignalFlutterBg] Location permissions not added on AndroidManifest file >= M
I/flutter (28779): OneSignal.Location.requestPermission did not throw.

Details

Motivation

Some apps use OneSignal push and in-app messages without OneSignal.Location. This demo provides a small runnable app for validating that push still works when the native OneSignal location module is excluded.

Scope

• Adds examples/demo-no-location with minimal Flutter UI and native iOS/Android projects.
• The demo documents running builds with ONESIGNAL_DISABLE_LOCATION=true.
• No core SDK behavior changes are included in this PR; it is stacked on fadi/sdk-4194.

Testing

Manual testing

• Validated the SPM manifest after restacking/fixing the branch.
• Verified ONESIGNAL_DISABLE_LOCATION=1 swift package dump-package excludes OneSignalLocation.

Affected code checklist

• Notifications
• In-App Messaging

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
• I have reviewed this PR myself, ensuring it meets each checklist item

Made with Cursor

[sherwinski]

@claude review once