Fix: Block style variations not rendering in Site Editor Patterns page

[Mustafabharmal]

What?

Block style variations (e.g. the outline button) were not rendering in the Site Editor > Patterns page, they displayed as the default style instead.

Closes #76089

Why?

The useBlockStyleVariation hook reads settings[globalStylesDataKey] to generate per-block variation CSS via toStyles({ variationStyles: true }). This Symbol key is set by useBlockEditorSettings in the main editor provider path, but the Patterns page uses a separate ExperimentalBlockEditorProvider whose settings are built by usePatternSettings. That function spreads raw storedSettings from the edit-site store (PHP-initialized, carries no Symbol keys), so settings[globalStylesDataKey] was always undefined, no variation CSS was ever generated.

How?

Pass mergedConfig.styles (from useGlobalStyles(), already used in the same hook) as [ globalStylesDataKey ] in the pattern preview settings. This is the exact same data the main editor path uses.

Testing Instructions

1. Activate TT5 theme
2. Go to Editor > Patterns
3. Select Call to action
4. View patterns

Screenshots or screencast

Before	After

[github-actions]

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Co-authored-by: Mustafabharmal <mustafabharmal@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>
Co-authored-by: bgardner <bgardner@git.wordpress.org>

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