Copilot test - Migrate legacy nav

[amoore108]

Resolves JIRA:

Summary

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Code changes

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Testing

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[Copilot]

Pull request overview

Migrates the Navigation component off #psammead/psammead-navigation onto local, in-repo equivalents, updating styling and tests/snapshots to match the new structure for both Canonical and AMP navigation.

Changes:

• Replaced Psammead navigation primitives with new local components (NavigationWrapper, ScrollableNavigation, NavigationList, DropdownNavigation).
• Updated navigation styling (divider rendering, focus/hover indicators, scrollable gradient) and adjusted Canonical/AMP renderers accordingly.
• Updated Jest tests/snapshots and bundle size thresholds; allowed AMP’s on attribute in ESLint config.

Reviewed changes

Copilot reviewed 17 out of 19 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/app/components/Navigation/index.tsx	Swaps list primitives to local NavigationList / DropdownList components.
src/app/components/Navigation/index.styles.ts	Refactors divider and focus/gradient-related styling; removes legacy menuButton styles.
src/app/components/Navigation/index.canonical.tsx	Replaces Psammead Navigation/ScrollableNavigation/dropdown/menu button with local wrappers.
src/app/components/Navigation/index.canonical.test.tsx	Updates assertion to match new dropdown height implementation (style vs attribute).
src/app/components/Navigation/index.amp.tsx	Replaces Psammead AMP navigation components with local wrappers and dropdown/menu button.
src/app/components/Navigation/snapshots/index.test.tsx.snap	Snapshot updates for structural/style changes from local navigation components.
src/app/components/Navigation/snapshots/index.canonical.test.tsx.snap	Canonical snapshot updates for new component structure/styles.
src/app/components/Navigation/snapshots/index.amp.test.tsx.snap	AMP snapshot updates for new component structure/styles.
src/app/components/Navigation/ScrollableNavigation/index.tsx	New scrollable nav wrapper with tracking-friendly data-e2e and direction/id support.
src/app/components/Navigation/ScrollableNavigation/index.styles.ts	New scrollable nav styles (overflow, scrollbar hiding, focus indicator, LTR/RTL gradient).
src/app/components/Navigation/NavigationWrapper/index.tsx	New <nav> wrapper replacing Psammead Navigation, including AMP open-class support.
src/app/components/Navigation/NavigationWrapper/index.styles.ts	Styles for wrapper layout and open-state background handling.
src/app/components/Navigation/NavigationList/index.tsx	New list + list item rendering (active/current-page handling, tracking prop spreading).
src/app/components/Navigation/NavigationList/index.styles.ts	Styles for list/list item/link states and current-page indicator.
src/app/components/Navigation/DropdownNavigation/types.d.ts	Adds AMP typing shims for amp-state and the on attribute.
src/app/components/Navigation/DropdownNavigation/index.tsx	New dropdown/menu button implementations for Canonical + AMP.
src/app/components/Navigation/DropdownNavigation/index.styles.ts	Styles for dropdown container/list and menu button (moved from legacy nav styles).
scripts/bundleSize/bundleSizeConfig.js	Updates expected bundle size thresholds after navigation refactor.
.eslintrc.js	Allows AMP on attribute in JSX a11y prop allowlist.