Fix dx serve proxying of websocket connections established from the browser (#3895)

* better ws request detection

* proxy ws connections

* improve naming

* perform case-insensitive header comparison

* preserve request headers when proxying websocket connection

* avoid side effects in conversion function

* fix websocket proxying for axum 0.8

* remove redundant conversions

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Co-authored-by: Evan Almloff <evanalmloff@gmail.com>

packages/cli/Cargo.toml

@@ -41,6 +41,7 @@ html_parser = { workspace = true }
 cargo_metadata = { workspace = true }
 tokio = { workspace = true, features = ["full"] }
 tokio-stream = { workspace = true }
+tokio-tungstenite = { workspace = true }
 chrono = { workspace = true }
 anyhow = { workspace = true }
 hyper = { workspace = true }