Allow middleware to redirect after downstream errors

[AyushCoder9]

update compose so middleware can replace error responses when context.error is set, enabling patterns like c.redirect() after an error add regression test covering the /hello?name=error scenario to ensure middleware can trigger a redirect post-error captures the behavior reported in #4530 where redirects triggered in middleware were ignored after an error

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 91.52%. Comparing base (342ff3b) to head (3ded05b).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4540   +/-   ##
=======================================
  Coverage   91.52%   91.52%           
=======================================
  Files         172      172           
  Lines       11221    11221           
  Branches     3255     3255           
=======================================
  Hits        10270    10270           
  Misses        950      950           
  Partials        1        1           

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