Extract search form into its own live component

[hackartisan]

Summary or User Story

According to our wireframes the search form should be visually integrated with the header and present on all current pages. To support this we should extract it into its own live component. Search filters should continue to only be visible / usable on the search results page.

Acceptance Criteria

• search form is its own live component
• search form is included on home page, search results page, and item view page

Implementation details

• We should be able to separate the search form from the filter submission because we have all the state we need in the url params.
• Try putting it in its own layout file, we expect there may be pages on which we want a header but not an item search form (like maybe a set or collection page wouldn't have one)

First step