Switch segment prefetch cache miss response from 204 to 404 (#92751)
The original reason for using 204 was to prevent segment cache misses
from appearing as errors in the browser network panel, e.g. if you
prefetch a same-origin link that happens to route to a different app on
the same domain. However, in output: export mode, we can't use custom
status codes — responses are served as static files, so we're limited to
standard HTTP semantics. Using 404 lets the server-driven and static
deployment strategies converge on the same client-server protocol. The
network panel noise is a minor, non-essential compromise.
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next.js
09353918 - Switch segment prefetch cache miss response from 204 to 404 (#92751)
