oddsrelay 0.1.0

• First release. One function for each GET route of the OddsRelay API, from or_odds() and or_raw() to or_usage() and or_healthz().
• The key comes from ODDSRELAY_KEY or a .key argument and travels only in the Authorization header. A filter named like a key is refused before anything is sent, so the key never lands in a URL.
• Replies are asked for gzip-compressed. Each URL’s ETag is kept for the session, so an unchanged reply comes back as a 304 that spends no tokens, returned as the body you already had with attr(x, "not_modified") set to TRUE.
• A 429 is retried after its Retry-After seconds, three requests in all.
• Every refusal signals a condition classed by its error code and status, carrying request_id; a 402 also carries cost, remaining and resets_at.
• The token and rate limit headers ride on every result as attributes. Printing a result shows the body and one line of tokens.