feat: unify php_server logic (#2499)
Currently the concept of a `php_server` only exists on the caddy side
and not the FrankenPHP side.
Lately we have been moving more and more in a direction of scoping
requests or workers to specific `php_server` blocks.
This PR is an attempt at refactoring the current `php_server` logic so
it is properly mirrored on the FrankenPHP side without BC breaks for
library users (and to prevent future bugs like mentioned in #2487)
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Signed-off-by: Alexander Stecher <45872305+AlliBalliBaba@users.noreply.github.com>
Co-authored-by: Marc <m@pyc.ac>
Co-authored-by: Nicolas Grekas <nicolas.grekas@gmail.com>
