Rack 3 requires that response headers use lower case keys. To support
applications designed for Rack < 3, Roda by default uses Rack::Headers
for response headers, which will automatically lower case keys. This
is suboptimal for performance. The plain_hash_response_headers
plugin allows using a plain hash for response headers, but in order
to use it, you must ensure that all response header keys are already
lower case. So change all response header keys to lower case.
Unfortunately, committee is not rack 3 compliant and does not
support lower case response header keys. It indexes into response
headers with Content-Type instead of content-type, which breaks on
rack 3 unless the headers hash is automatically lower casing keys.
Work around this issue by setting the Content-Type header before
calling committee's response validation, and deleting it afterward.
This can be removed after committee is fixed.
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