chore(web): unique ID generation (#9932)

* chore(web): automatically generate unique IDs

* fix: revert changes to Slider

* chore: add test for id store

web/src/lib/stores/unique-id.store.spec.ts

@@ -0,0 +1,14 @@
+import { uniqueIdStore } from '$lib/stores/unique-id.store';
+
+describe('uniqueIdStore', () => {
+  afterEach(() => {
+    uniqueIdStore.update(() => -1);
+  });
+
+  it('should generate unique ids', () => {
+    const { generateId } = uniqueIdStore;
+    const ids = [generateId(), generateId(), generateId()];
+
+    expect(ids).toEqual(['id-0', 'id-1', 'id-2']);
+  });
+});

web/src/lib/stores/unique-id.store.ts

@@ -0,0 +1,16 @@
+import { get, writable } from 'svelte/store';
+
+function createIdStore() {
+  const { subscribe, update } = writable(-1);
+
+  return {
+    subscribe,
+    update,
+    generateId: () => {
+      update((value) => value + 1);
+      return `id-${get(uniqueIdStore)}`;
+    },
+  };
+}
+
+export const uniqueIdStore = createIdStore();