multiple fullstack nits/cleanups before release (#4852)

* feat: `:arg` syntax for serverfn

* add better decode/encode verify message

* allow catch-all query args

* add rebind

* implement websocket frames for `Streaming`

* fix lazy init

* wip... serverfnstate

* wip...

* wip: serverfns require Send/Sync, let's fix that

* wip...

* small cleanup

* fix hang by actually spawning the tokio task

* clippy

* fix parameter catchall binding

* fix lychee

* doc tests

packages/fullstack-core/src/error.rs

@@ -162,6 +162,20 @@ impl From<RequestError> for ServerFnError {
     }
 }
 
+impl From<ServerFnError> for HttpError {
+    fn from(value: ServerFnError) -> Self {
+        let status = StatusCode::from_u16(match &value {
+            ServerFnError::ServerError { code, .. } => *code,
+            _ => 500,
+        })
+        .unwrap_or(StatusCode::INTERNAL_SERVER_ERROR);
+        HttpError {
+            status,
+            message: Some(value.to_string()),
+        }
+    }
+}
+
 impl From<HttpError> for ServerFnError {
     fn from(value: HttpError) -> Self {
         ServerFnError::ServerError {