Add foreground service, some cleanup, and start websocket server

src/service/Foreground.ts

@@ -0,0 +1,24 @@
+import {Unit} from '../lifecycle/Unit'
+import {Inject} from '../di'
+import {Logging} from './Logging'
+import * as process from 'process'
+
+export class Foreground extends Unit {
+    @Inject()
+    protected readonly logging!: Logging
+
+    protected resolver?: () => unknown
+
+    public up(): Promise<void> {
+        return new Promise<void>(res => {
+            this.resolver = res
+            this.logging.success(`Application started! Press ^C or send SIGINT to stop.`)
+            process.stdin.resume()
+            process.on('SIGINT', res)
+        })
+    }
+
+    public down(): void {
+        this.resolver?.()
+    }
+}