feat: Deprecate 'Deno.serveHttp' API (#21874)

`Deno.serveHttp` is now deprecated. 

Users should migrate to `Deno.serve` API.

cli/tsc/dts/lib.deno.ns.d.ts

@@ -5286,7 +5286,9 @@ declare namespace Deno {
   /** The event yielded from an {@linkcode HttpConn} which represents an HTTP
    * request from a remote client.
    *
-   * @category HTTP Server */
+   * @category HTTP Server
+   * @deprecated Use {@linkcode serve} instead.
+   */
   export interface RequestEvent {
     /** The request from the client in the form of the web platform
      * {@linkcode Request}. */
@@ -5305,7 +5307,9 @@ declare namespace Deno {
    * yields up {@linkcode RequestEvent} events, representing individual
    * requests on the HTTP server connection.
    *
-   * @category HTTP Server */
+   * @category HTTP Server
+   * @deprecated Use {@linkcode serve} instead.
+   */
   export interface HttpConn extends AsyncIterable<RequestEvent>, Disposable {
     /** The resource ID associated with this connection. Generally users do not
      * need to be aware of this identifier. */
@@ -5370,6 +5374,7 @@ declare namespace Deno {
    * used elsewhere. In such a case, this function will fail.
    *
    * @category HTTP Server
+   * @deprecated Use {@linkcode serve} instead.
    */
   export function serveHttp(conn: Conn): HttpConn;