Add CourtListener search through ICU

[isomorphisms]

Boundary

Adds the first edric courtlistener search QUERY slice. Idriç owns CLI parsing, CourtListener request meaning, JSON decoding, typed results, and output. ICU remains the only HTTP/TLS implementation.

Receipts

• typed v4 request construction
• typed fixture decode for caseName, court, dateFiled, citation, and absolute_url
• malformed query refusal
• network/transport failure
• non-2xx refusal
• invalid JSON refusal
• source check preventing a second HTTP implementation
• live Brown v. Board of Education request through ICU in CI

The next endpoint noted for implementation is dockets, then docket-entries.