Provide suggestions as you type for Search bar

[AbrilRBS]

It may be a superficial observation, yet I appreciated the feature in the previous version where it offered suggestions while typing. This feature proves valuable for lengthy or intricate library names, and it aids in the discovery of new libraries as well.

Originally posted by @acano15 in #85 (comment)

[valgur]

The list of matching packages already auto-updates when typing in the search bar on the search results page, but not on the landing page. IMO, this is a sufficient alternative for the suggestions dropdown that existed in the old version of ConanCenter. My suggestion would be to simply add the auto-updating behavior to the landing page as well.

On a related note, the auto-updating triggers too eagerly right now. When the search bar is cleared on the search results page, it returns and displays all existing packages in CC. This brings the page to a crawl when viewed from a mobile browser. A minimum limit of two characters would be more sensible.