Adds hierarchical grouping and entity resolution support

Enhances calendar rendering with dynamic parent-child relationships between entities

Introduces EntityResolver for dot-notation references
Supports belongsTo configuration in grouping
Implements flexible filtering across hierarchical entities

Improves rendering flexibility for complex organizational structures

src/v2/storage/IndexedDBContext.ts

@@ -10,7 +10,7 @@ import { IStore } from './IStore';
  */
 export class IndexedDBContext {
   private static readonly DB_NAME = 'CalendarV2DB';
-  private static readonly DB_VERSION = 2;
+  private static readonly DB_VERSION = 3;
 
   private db: IDBDatabase | null = null;
   private initialized: boolean = false;

src/v2/storage/teams/TeamService.ts

@@ -0,0 +1,44 @@
+import { ITeam, EntityType, IEventBus } from '../../types/CalendarTypes';
+import { TeamStore } from './TeamStore';
+import { BaseEntityService } from '../BaseEntityService';
+import { IndexedDBContext } from '../IndexedDBContext';
+
+/**
+ * TeamService - CRUD operations for teams in IndexedDB
+ *
+ * Teams define which resources belong together for hierarchical grouping.
+ * Extends BaseEntityService for standard entity operations.
+ */
+export class TeamService extends BaseEntityService<ITeam> {
+  readonly storeName = TeamStore.STORE_NAME;
+  readonly entityType: EntityType = 'Team';
+
+  constructor(context: IndexedDBContext, eventBus: IEventBus) {
+    super(context, eventBus);
+  }
+
+  /**
+   * Get teams by IDs
+   */
+  async getByIds(ids: string[]): Promise<ITeam[]> {
+    if (ids.length === 0) return [];
+    const results = await Promise.all(ids.map(id => this.get(id)));
+    return results.filter((t): t is ITeam => t !== null);
+  }
+
+  /**
+   * Build reverse lookup: resourceId → teamId
+   */
+  async buildResourceToTeamMap(): Promise<Record<string, string>> {
+    const teams = await this.getAll();
+    const map: Record<string, string> = {};
+
+    for (const team of teams) {
+      for (const resourceId of team.resourceIds) {
+        map[resourceId] = team.id;
+      }
+    }
+
+    return map;
+  }
+}

src/v2/storage/teams/TeamStore.ts

@@ -0,0 +1,13 @@
+import { IStore } from '../IStore';
+
+/**
+ * TeamStore - IndexedDB ObjectStore definition for teams
+ */
+export class TeamStore implements IStore {
+  static readonly STORE_NAME = 'teams';
+  readonly storeName = TeamStore.STORE_NAME;
+
+  create(db: IDBDatabase): void {
+    db.createObjectStore(TeamStore.STORE_NAME, { keyPath: 'id' });
+  }
+}