Feature/shared refactor (#1176)

* refactor: move most of the shared entities to @start8labs/shared library

frontend/projects/shared/src/services/destroy.service.ts

@@ -0,0 +1,13 @@
+import { Injectable, OnDestroy } from '@angular/core'
+import { ReplaySubject } from 'rxjs'
+
+/**
+ * Observable abstraction over ngOnDestroy to use with takeUntil
+ */
+@Injectable()
+export class DestroyService extends ReplaySubject<void> implements OnDestroy {
+  ngOnDestroy() {
+    this.next()
+    this.complete()
+  }
+}

frontend/projects/shared/src/services/emver.service.ts

@@ -0,0 +1,18 @@
+import { Injectable } from '@angular/core'
+import * as emver from '@start9labs/emver'
+
+@Injectable({
+  providedIn: 'root',
+})
+export class Emver {
+  constructor() {}
+
+  compare(lhs: string, rhs: string): number {
+    if (!lhs || !rhs) return null
+    return emver.compare(lhs, rhs)
+  }
+
+  satisfies(version: string, range: string): boolean {
+    return emver.satisfies(version, range)
+  }
+}