Make usage of the search icon more consistent and meaningful

[afercia]

Description

Similarly to #62873, to provide cohesive design language in the editor UI the usage of icons should be consistent. Icons should identify unique features or, at least, similar features.

The search icon is one of the most popular and familiar icons on the web. I'm not sure it's ideal to use it for features other than, well, a search.

In the Site editor it is used also for the Command palette. This is potentially confusing for users and particularly disorienting when the UI shows anoter search icon close to the command palette one. Actually, in some cases, the editor shows two very close search icons that are associated with entirely different features. Example screenshot:

I'd tend to think the command palette should not use the search icon in the first place.

Another occurrence of icon={ search } is in the Image editor. When editing an image, the block toolbar shows a search icon that is associated with the Zoom feature. Screenshot:

Also in this case I'd argue the search icon isn't the best one to use. Usually, zoom icons use a lens that either contains either a plus or minus sign. Example from the Material design icons:

Step-by-step reproduction instructions

• Go to the Site editor > Pages.
• Observe that, regardless of whether the active view is List, Table, or Grid, the editor UI shows two search icon for two different features.
• Add an Image block, set an image, and click Crop in the block toolbar.
• Observe the toolbar shows a Zoom control with a search icon.

Screenshots, screen recording, code snippet

No response

Environment info

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Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes