Adds comprehensive mock data repositories and seeding infrastructure

Implements polymorphic data seeding mechanism for initial application setup

- Adds Mock repositories for Event, Booking, Customer, and Resource entities
- Creates DataSeeder to automatically populate IndexedDB from JSON sources
- Enhances index.ts initialization process with data seeding step
- Adds mock JSON data files for comprehensive test data

Improves offline-first and development testing capabilities

wwwroot/data/mock-resources.json

@@ -0,0 +1,80 @@
+[
+  {
+    "id": "EMP001",
+    "name": "camilla.jensen",
+    "displayName": "Camilla Jensen",
+    "type": "person",
+    "avatarUrl": "/avatars/camilla.jpg",
+    "color": "#9c27b0",
+    "isActive": true,
+    "metadata": {
+      "role": "master stylist",
+      "specialties": ["balayage", "color", "bridal"]
+    }
+  },
+  {
+    "id": "EMP002",
+    "name": "isabella.hansen",
+    "displayName": "Isabella Hansen",
+    "type": "person",
+    "avatarUrl": "/avatars/isabella.jpg",
+    "color": "#e91e63",
+    "isActive": true,
+    "metadata": {
+      "role": "master stylist",
+      "specialties": ["highlights", "ombre", "styling"]
+    }
+  },
+  {
+    "id": "EMP003",
+    "name": "alexander.nielsen",
+    "displayName": "Alexander Nielsen",
+    "type": "person",
+    "avatarUrl": "/avatars/alexander.jpg",
+    "color": "#3f51b5",
+    "isActive": true,
+    "metadata": {
+      "role": "master stylist",
+      "specialties": ["men's cuts", "beard", "fade"]
+    }
+  },
+  {
+    "id": "EMP004",
+    "name": "viktor.andersen",
+    "displayName": "Viktor Andersen",
+    "type": "person",
+    "avatarUrl": "/avatars/viktor.jpg",
+    "color": "#009688",
+    "isActive": true,
+    "metadata": {
+      "role": "stylist",
+      "specialties": ["cuts", "styling", "perms"]
+    }
+  },
+  {
+    "id": "STUDENT001",
+    "name": "line.pedersen",
+    "displayName": "Line Pedersen (Elev)",
+    "type": "person",
+    "avatarUrl": "/avatars/line.jpg",
+    "color": "#8bc34a",
+    "isActive": true,
+    "metadata": {
+      "role": "student",
+      "specialties": ["wash", "blow-dry", "basic cuts"]
+    }
+  },
+  {
+    "id": "STUDENT002",
+    "name": "mads.larsen",
+    "displayName": "Mads Larsen (Elev)",
+    "type": "person",
+    "avatarUrl": "/avatars/mads.jpg",
+    "color": "#ff9800",
+    "isActive": true,
+    "metadata": {
+      "role": "student",
+      "specialties": ["wash", "styling assistance"]
+    }
+  }
+]