feat: exclude Teams from defaults + GUID resolution in explain

- Add Teams to noisy services excluded by default (frontend + backend ask)
- Exchange, SharePoint, and Teams now unchecked by default in filters
- Enhance explain endpoint with GUID resolution:
  * Extract UUIDs from raw event JSON recursively
  * Resolve directory objects via Graph API (user, group, SP, device)
  * Include resolved names in LLM prompt so explanations reference
    human-readable names instead of raw GUIDs
- Add asyncio import for to_thread wrapper around sync Graph calls

backend/frontend/index.html

@@ -522,7 +522,7 @@
             const saved = localStorage.getItem('aoc_filters');
             if (!saved && this.options.services.length) {
               // Default: exclude noisy high-volume services
-              const noisy = ['Exchange', 'SharePoint'];
+              const noisy = ['Exchange', 'SharePoint', 'Teams'];
               this.filters.selectedServices = this.options.services.filter((s) => !noisy.includes(s));
             } else if (saved) {
               try {
@@ -617,7 +617,7 @@
         },
 
         clearFilters() {
-          const noisy = ['Exchange', 'SharePoint'];
+          const noisy = ['Exchange', 'SharePoint', 'Teams'];
           this.filters = { actor: '', selectedServices: this.options.services.filter((s) => !noisy.includes(s)), search: '', operation: '', result: '', start: '', end: '', limit: 100, includeTags: '', excludeTags: '' };
           this.saveFilters();
           this.resetPagination();