feat: implement websocket-stream for journal server

Integrate `websocket-stream` to handle MQTT broker upgrades in the
CLI and add granular connection status tracking to the UI.

- Add `websocket-stream` dependency
- Update CLI to use `websocket-stream` for socket upgrades
- Enhance `journalStream` store with `connectionStatus` and
  `connectionError` states
- Add visual connection status indicators to `App` and `JournalPanel`

src/cli/journal.ts

@@ -20,6 +20,7 @@ import {
 } from "fs";
 import type { Server as HttpServer } from "http";
 import type { AedesPublishPacket } from "aedes";
+import websocketStream from "websocket-stream";
 
 // ---------------------------------------------------------------------------
 // Types
@@ -106,7 +107,11 @@ export async function createJournalServer(
 
   httpServer.on("upgrade", (req, socket, head) => {
     wsServer.handleUpgrade(req, socket, head, (ws) => {
-      broker.handle(ws as unknown as import("net").Socket);
+      // websocket-stream's types reference an older ws version; cast works.
+      const stream = websocketStream(
+        ws as unknown as Parameters<typeof websocketStream>[0],
+      );
+      broker.handle(stream);
     });
   });