add functionality and styles for toggling page content

[eshaben]

This pull request introduces a new page-level toggle feature.

Page-level toggle feature:

• Added new template toggle-page.html to support page-level tab toggling, including logic to move tabbed labels next to the page title and synchronize tab selection with Table of Contents visibility.
• Introduced toggle-page.css with styles for the page-level toggle, including pill-style tab labels, responsive layout, and active tab highlighting.

[Copilot]

Pull Request Overview

This PR adds functionality and styles for toggling page content using a page-level toggle interface. The implementation moves tabbed labels into an h1 wrapper to create a pill-style toggle that controls content visibility and updates the table of contents accordingly.

• Adds a new HTML template that manipulates page content to relocate tabbed labels next to the page title
• Implements JavaScript functionality to manage toggle states and TOC visibility
• Introduces CSS styles for a pill-style toggle interface with smooth transitions

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
material-overrides/toggle-page.html	New template that extends main.html with content manipulation and toggle functionality
material-overrides/assets/stylesheets/toggle-page.css	New stylesheet defining pill-style toggle appearance and responsive behavior
material-overrides/assets/stylesheets/polkadot.css	Updates existing styles to support the new toggle functionality and fix spacing issues

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