add: redesign built mostly with Neynar APIs

[dylsteck]

the redesign of Casterscan includes:

• a live cast firehose as either a list or grid
• a dedicated page per cast that shows a table of details as well as responses across api/hub providers
• a cast action that links any warpcast cast to its details page on casterscan

this redesign was built ~90% with Neynar APIs.

some future ideas include:

• expand to more response providers and show response times
• show user profiles as well as user casts on the profile page (could potentially do this for channels too)
• show other data types like the structure of a signer, or all casts from a signer
• allow users to put a hash/warpcast url in the 'search' bar
• actual search/discovery?