use hostname from patchDB as default server name (#1758)

* replace offline toast with global indicator

* use hostname from patchDB as default server name

* add alert to marketplace delete and reword logout alert

frontend/projects/ui/src/app/services/server-name.service.ts

@@ -0,0 +1,30 @@
+import { Injectable } from '@angular/core'
+import { PatchDbService } from './patch-db/patch-db.service'
+import { combineLatest, filter, map, Observable } from 'rxjs'
+
+export interface ServerNameInfo {
+  current: string
+  default: string
+}
+
+@Injectable({ providedIn: 'root' })
+export class ServerNameService {
+  private readonly chosenName$ = this.patch.watch$('ui', 'name')
+  private readonly hostname$ = this.patch
+    .watch$('server-info', 'hostname')
+    .pipe(filter(Boolean))
+
+  readonly name$: Observable<ServerNameInfo> = combineLatest([
+    this.chosenName$,
+    this.hostname$,
+  ]).pipe(
+    map(([chosen, hostname]) => {
+      return {
+        current: chosen || hostname,
+        default: hostname,
+      }
+    }),
+  )
+
+  constructor(private readonly patch: PatchDbService) {}
+}