On image hover, the "reaction" button should be first, not "download"

#### Description

When hovering over an image in a channel, the image toolbar puts the "download" button first. This is not the common use case, and I find myself mistakenly clicking it when I intend to use the *strongly* dominant use case: adding a reaction.

Users in typical channels will always be more likely to react to an image first. To fix, simply swap the "download" and "reaction" buttons.

#### Version information

Desktop Version 1.7.34

Start by locating the image hover toolbar in the TypeScript frontend and identify the controls currently rendered as download and reaction. Swap their order so reaction appears first, then verify in the image hover UI that the toolbar order matches the requested behavior.

Written by the indexing model from the issue text.