Change run loop observer mode to common modes to prevent freezing on iOS

[rapporian]

Proposed fix for issue #1162 - Needs maintainer validation.

On iOS, all events are blocked while the user is scrolling. This breaks every Tao-based iOS app that needs real-time updates during scroll.

Affected

• Signal/state updates
• Async task completions
• Cross-thread UI communication

iOS run loop modes:

Mode	When Active	DefaultMode Observers	CommonModes Observers
kCFRunLoopDefaultMode	Normal	✅ Fire	✅ Fire
UITrackingRunLoopMode	Scrolling	❌ Don't fire	✅ Fire

The run loop observers are registered for kCFRunLoopDefaultMode only. During scroll, iOS switches to UITrackingRunLoopMode — observers aren't registered for that mode, so they don't fire and events don't get processed.

[github-actions[bot]]

Package Changes Through 7678b4f6e9c2be36a98529936cab615aff2aeb2b

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