fix: do not re-escape cookies collected from fetch calls during SSR

[Conduitry]

Fixes #11687. We want cookies set by APIs called by fetch during SSR loads to be carried over as-is into the browser. We do this by telling set-cookie-parser to not attempt to URL decode the cookies set in the external API, and then telling cookie to not URL encode the cookie as it's constructing the outgoing header.

This appeared to work in my manual tests, but I was struggling with Playwright and haven't written formal tests yet. I'll try to do so in the morning.

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[Conduitry]

Finally got around to pushing a test. This test fails on main as the cookie value ends up being %22foo%22 instead of "foo". Note that the test also skips the fetch during the client-side load, as this would overwrite the (previously incorrect) value from SSR with a correct value from the browser's fetch.

[eltigerchino]

Thank you!