Fix incorrect C++/WinRT Frame instantiation syntax in navigation tutorial

[Copilot]

The C++/WinRT code snippet in the two-page navigation tutorial used Frame rootFrame = Frame(); — a C# pattern (new Frame()) with new removed, which is not valid idiomatic C++/WinRT.

Change

Replaced with the correct brace-initialization form, which invokes the WinRT activation factory's default constructor:

// Before (incorrect — C# idiom without `new`)
Frame rootFrame = Frame();

// After (correct C++/WinRT idiom)
Frame rootFrame{};

This is consistent with how other C++/WinRT examples across the docs repo instantiate WinRT runtime classes (e.g., Frame rootFrame{ nullptr }; for null handles, Frame rootFrame{}; for default-constructed objects).

• Fixes The wrong string of code. #5326

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Learn Build status updates of commit 751597b:

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[learn-build-service-prod]

Learn Build status updates of commit 0097f88:

✅ Validation status: passed

File	Status	Preview URL	Details
hub/apps/develop/ui/navigation/navigate-between-two-pages.md	✅Succeeded

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[Copilot]

Pull request overview

This PR corrects the C++/WinRT sample in the “navigate between two pages” tutorial so the Frame is instantiated using idiomatic C++/WinRT brace-initialization (Frame rootFrame{};) rather than the non-idiomatic/incorrect Frame rootFrame = Frame();.

Changes:

• Updated the C++/WinRT OnLaunched snippet to use Frame rootFrame{}; for proper default activation.