Expand description
Shared HTTP scaffolding for vendor API clients.
Holds the reqwest::Client, base URL, and bearer token; provides the
per-request tracing/auth/error-mapping boilerplate. Vendor clients embed an
HttpClient, build their own request bodies/queries, then call
HttpClient::send to dispatch and apply the standard instrumentation.
Envelope parsing stays in the vendor module since each API’s response shape
differs.