[Bug] Hover effect on tiles gets stuck

**Packages & versions**

Media 0.7.0

**Describe the bug**

On the Control Panel when viewing media for a publication, in some cases you can have multiple image/video tiles displaying the hover effect.

**Reproduction steps**

1. Go to Publication
2. Move cursor rapidly over the window

**Expected behavior**

Only 1 can ever have the hover effect. Ideally when the cursor leaves the window all disappear.

**Additional context**

I think we can achieve this by adding the mouse position handlers to the window or page, rather than each individual item, and then passing the positions down to each tile. Then the components themselves can check if they are within those coordinates.

Start in the Control Panel media view and trace the hover handlers for image and video tiles. Reproduce the bug by moving the cursor rapidly over the window, then verify that only the tile under the cursor has the hover effect and that all tiles clear when the cursor leaves the window.

Written by the indexing model from the issue text.