chore: ITemplatedParentProvider removal (backport #18443)

[mergify]

GitHub Issue (If applicable): n/a

PR Type

What kind of change does this PR introduce?

• Refactoring (no functional changes, no api changes)

What is the new behavior?

follow-up of #17645
removing ITemplatedParentProvider and relevant codegen in DOGenerator, replaced with direct implementations in DOStore.
add a few more tests against regressions found in the tp rework.
ninja-fix: native Frame not being initialized.

PR Checklist

Please check if your PR fulfills the following requirements:

• Docs have been added/updated which fit documentation template (for bug fixes / features)
• Unit Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• Validated PR Screenshots Compare Test Run results.
• Contains NO breaking changes
• Associated with an issue (GitHub or internal) and uses the automatic close keywords.
• Commits must be following the Conventional Commits specification.

Other information

With changes from this PR and #17645, there are a few notable changes to the templated-parent system:

1. DO::TemplatedParent dependency property, ::OnTemplatedParentChanged(e), and DOStore.SetTemplatedParent(FrameworkElement) are fully deprecated. They are no longer called by the Uno framework, and should not be used anymore. They are, however, still temporarily kept in v5.5.0 to avoid binary changes until next major version.
2. Access to the templated-parent, can now be made through the following code:

   // within uno.ui assembly
   DependencyObject DependencyObjectExtensions.GetTemplatedParent(this DependencyObject @do);
   void DependencyObjectExtensions.SetTemplatedParent(this DependencyObject @do, DependencyObject tp);
   DependencyObject FrameworkElement.GetTemplatedParent();
   void FrameworkElement.GetTemplatedParent(DependencyObject tp);
   // outside uno
   (do_or_fe as IDependencyObjectStoreProvider)?.Store.GetTemplatedParent2(); // note: the -2 suffix here is to distinguished between the old deprecated method.
   //(do_or_fe as IDependencyObjectStoreProvider)?.Store.SetTemplatedParent2(null); // you shouldnt need this

3. override to OnTemplatedParentChanged, should be replaced by OnLoaded()(within uno.ui assembly) or FE.Loaded += ...(outside uno).

   ---

   This is an automatic backport of pull request chore: ITemplatedParentProvider removal #18443 done by Mergify.

[unodevops]

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[unodevops]

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[nventive-devops]

The build 143357 did not find any UI Test snapshots differences.