TUN-9470: Add OriginDialerService to include TCP

Adds an OriginDialerService that takes over the roles of both DialUDP and DialTCP 
towards the origin. This provides the possibility to leverage dialer "middleware"
to inject virtual origins, such as the DNS resolver service.

DNS Resolver service also gains access to the DialTCP operation to service TCP
DNS requests.

Minor refactoring includes changes to remove the needs previously provided by
the warp-routing configuration. This configuration cannot be disabled by cloudflared
so many of the references have been adjusted or removed.

Closes TUN-9470

ingress/origin_connection.go

@@ -19,7 +19,7 @@ import (
 type OriginConnection interface {
 	// Stream should generally be implemented as a bidirectional io.Copy.
 	Stream(ctx context.Context, tunnelConn io.ReadWriter, log *zerolog.Logger)
-	Close()
+	Close() error
 }
 
 type streamHandlerFunc func(originConn io.ReadWriter, remoteConn net.Conn, log *zerolog.Logger)
@@ -48,16 +48,7 @@ func (tc *tcpConnection) Write(b []byte) (int, error) {
 		}
 	}
 
-	nBytes, err := tc.Conn.Write(b)
-	if err != nil {
-		tc.logger.Err(err).Msg("Error writing to the TCP connection")
-	}
-
-	return nBytes, err
-}
-
-func (tc *tcpConnection) Close() {
-	tc.Conn.Close()
+	return tc.Conn.Write(b)
 }
 
 // tcpOverWSConnection is an OriginConnection that streams to TCP over WS.
@@ -75,8 +66,8 @@ func (wc *tcpOverWSConnection) Stream(ctx context.Context, tunnelConn io.ReadWri
 	wsConn.Close()
 }
 
-func (wc *tcpOverWSConnection) Close() {
-	wc.conn.Close()
+func (wc *tcpOverWSConnection) Close() error {
+	return wc.conn.Close()
 }
 
 // socksProxyOverWSConnection is an OriginConnection that streams SOCKS connections over WS.
@@ -95,5 +86,6 @@ func (sp *socksProxyOverWSConnection) Stream(ctx context.Context, tunnelConn io.
 	wsConn.Close()
 }
 
-func (sp *socksProxyOverWSConnection) Close() {
+func (sp *socksProxyOverWSConnection) Close() error {
+	return nil
 }