Persist show context state

[ericokuma]

Persists the "show context for all measures" toggle state to the lb_ctx URL parameter. This ensures the toggle's state is preserved when sharing links or revisiting the dashboard, improving user experience by remembering their preference (APP-638).

Checklist:

• [x] Covered by tests
• [x] Ran it and it works as intended
• [x] Reviewed the diff before requesting a review
• [x] Checked for unhandled edge cases
• [x] Linked the issues it closes
• [ ] Checked if the docs need to be updated. If so, create a separate Linear DOCS issue
• [ ] Intend to cherry-pick into the release branch
• [ ] I'm proud of this work!

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Linear Issue: APP-638

 

[cursor[bot]]

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