- normalise self.key_header via to_lower before the req.headers lookup
- req.headers keys are already lowercased on read (internal/parse.wo);
the documented key_header: "Idempotency-Key" never matched, silently
disabling idempotency (falls through to inner.handle) on every request
- key/digest lookups use the normalised name consistently
- digest now always includes method+path, body appended only when
include_body is set -- a bare "" digest under include_body:false
previously matched any other request reusing the same key
- log a genuine pool_begin trap instead of silently folding it into 503
- update the two doc comments describing the old, unsafe shape
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
(cherry picked from commit 91099cfbb2fb9a2d351894e444fed306b25557d5)
shoney.arickathil
899f2c604e