script: Implement parsing of Link HTTP headers (#39052)

The Link HTTP header can do the same as link elements,
in that they can preload/prefetch/etc... This implements
the basics of header parsing and hooks it up for preload.

Note that we use a new nom-rfc8288 crate that implements
the parsing behavior. However, that crate is too strict
in that empty attributes (;; as part of the header) are
discarded and resulting in a parsing failure. Therefore,
we use its lenient parsing mode.

Part of #35035

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Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com>
Signed-off-by: Tim van der Lippe <TimvdLippe@users.noreply.github.com>
Co-authored-by: Josh Matthews <josh@joshmatthews.net>

components/script/Cargo.toml

@@ -93,6 +93,7 @@ mime = { workspace = true }
 mime_guess = { workspace = true }
 net_traits = { workspace = true }
 nom = { workspace = true }
+nom-rfc8288 = { workspace = true }
 num-traits = { workspace = true }
 num_cpus = { workspace = true }
 parking_lot = { workspace = true }