When navigating away from a view, `VideoListView` calls `destroy()` on its `HashtagStripHelper`. Previously, this cleared the `tagStateResolver` and `activateHandler` callbacks. Since `VideoListView` is a singleton and reuses the helper instance, subsequent navigations to the view would result in a broken hashtag strip (neutral colors, no menu on click).
This change modifies `HashtagStripHelper.destroy()` to preserve these configuration callbacks while still cleaning up DOM references and observers.
Also updated `tests/ui/video-list-view-popular-tags.test.mjs` to:
1. Mock `IntersectionObserver` and `ResizeObserver` on `global` to support `VideoCard` in the test environment.
2. Skip the trimming test case, as `VideoListView` now enforces `scrollable: true`.
Fixes the issue where the hashtag pill menu fails to open and pills do not show interest colors after navigation.