fix(perps-controller): show chart by default on first Pro mode switch

[michalconsensys]

Explanation

Switching from Perps Lite to Pro remembered the last chart visibility setting, but the first switch into Pro used chartExpanded: false. That hid the chart by default and made it easy for users to miss that a chart existed.

This change expands the chart the first time a user enters Pro mode via setPerpsMode, then keeps their last chartExpanded preference on later Lite/Pro switches.

Implementation notes:

• Adds persisted hasEnteredProMode (default false) to distinguish first Pro entry from later visits.
• Hydrated state that already has a mode field (from a version that already supported Pro mode) is treated as a returning user so an existing hidden-chart preference is not overwritten after upgrade.
• DEFAULT_PRO_LAYOUT_PREFERENCES.chartExpanded stays false; the first-entry override lives in setPerpsMode rather than changing the static default.

References

• TAT-3782

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

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