Implements FilterTemplate system for event matching

Introduces flexible key-based filtering for calendar events across different view configurations

Adds new FilterTemplate class to:
- Define event matching rules based on view configuration
- Support multi-level grouping (team/resource/date)
- Handle dynamic key generation for columns and events

Enhances view configuration with explicit id properties and derived fields

src/v2/features/headerdrawer/HeaderDrawerRenderer.ts

@@ -4,6 +4,7 @@ import { CoreEvents } from '../../constants/CoreEvents';
 import { HeaderDrawerManager } from '../../core/HeaderDrawerManager';
 import { EventService } from '../../storage/events/EventService';
 import { DateService } from '../../core/DateService';
+import { FilterTemplate } from '../../core/FilterTemplate';
 import {
   IDragEnterHeaderPayload,
   IDragMoveHeaderPayload,
@@ -36,6 +37,7 @@ export class HeaderDrawerRenderer {
   private container: HTMLElement | null = null;
   private sourceElement: HTMLElement | null = null;
   private wasExpandedBeforeDrag = false;
+  private filterTemplate: FilterTemplate | null = null;
 
   constructor(
     private eventBus: IEventBus,
@@ -49,8 +51,12 @@ export class HeaderDrawerRenderer {
 
   /**
    * Render allDay events into the header drawer with row stacking
+   * @param filterTemplate - Template for matching events to columns
    */
-  async render(container: HTMLElement, filter: Record<string, string[]>): Promise<void> {
+  async render(container: HTMLElement, filter: Record<string, string[]>, filterTemplate: FilterTemplate): Promise<void> {
+    // Store filterTemplate for buildColumnKeyFromEvent
+    this.filterTemplate = filterTemplate;
+
     const drawer = container.querySelector('swp-header-drawer');
     if (!drawer) return;
 
@@ -150,14 +156,24 @@ export class HeaderDrawerRenderer {
   }
 
   /**
-   * Build columnKey from event fields
-   * This is the only place we construct columnKey from event data
+   * Build columnKey from event using FilterTemplate
+   * Uses the same template that columns use for matching
    */
   private buildColumnKeyFromEvent(event: ICalendarEvent, date?: Date): string {
-    const dateStr = this.dateService.getDateKey(date || event.start);
-    const segments: Record<string, string> = { date: dateStr };
-    if (event.resourceId) segments.resource = event.resourceId;
-    return this.dateService.buildColumnKey(segments);
+    if (!this.filterTemplate) {
+      // Fallback if no template - shouldn't happen in normal flow
+      const dateStr = this.dateService.getDateKey(date || event.start);
+      return dateStr;
+    }
+
+    // For multi-day events, we need to override the date in the event
+    if (date && date.getTime() !== event.start.getTime()) {
+      // Create temporary event with overridden start for key generation
+      const tempEvent = { ...event, start: date };
+      return this.filterTemplate.buildKeyFromEvent(tempEvent);
+    }
+
+    return this.filterTemplate.buildKeyFromEvent(event);
   }
 
   /**