Fix reload mode and streaming in 5.0 dev (#9269)

* Fix reload mode + streaming

* use api_prefix for reload

* add changeset

* comments

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>

.changeset/calm-planets-send.md

@@ -0,0 +1,7 @@
+---
+"@gradio/core": minor
+"@self/spa": minor
+"gradio": minor
+---
+
+feat:Fix reload mode and streaming in 5.0 dev

js/core/src/Blocks.svelte

@@ -315,7 +315,7 @@
 				) {
 					await app.post_data(
 						// @ts-ignore
-						`${app.config.root}/stream/${submit_map.get(dep_index).event_id()}`,
+						`${app.config.root + app.config.api_prefix}/stream/${submit_map.get(dep_index).event_id()}`,
 						{ ...payload, session_hash: app.session_hash }
 					);
 					return;
@@ -596,7 +596,7 @@
 					if (submit_map.has(dep_id)) {
 						app.post_data(
 							// @ts-ignore
-							`${app.config.root}/stream/${submit_map.get(dep_id).event_id()}/close`,
+							`${app.config.root + app.config.api_prefix}/stream/${submit_map.get(dep_id).event_id()}/close`,
 							{}
 						);
 					}

js/spa/src/Index.svelte

@@ -311,7 +311,7 @@
 		if (config.dev_mode) {
 			setTimeout(() => {
 				const { host } = new URL(api_url);
-				let url = new URL(`http://${host}/dev/reload`);
+				let url = new URL(`http://${host}${app.api_prefix}/dev/reload`);
 				stream = new EventSource(url);
 				stream.addEventListener("error", async (e) => {
 					new_message_fn("Error reloading app", "error");