feat(leads): implement reactive search for exhibitors and lead tracking

- Implemented V3-style reactive search (Local Cache -> Remote Revalidation) for exhibitors.
- Standardized search fields to 'name' for Exhibits and 'event_badge_full_name' for Lead Tracking.
- Refactored Leads UI with standardized search components and grid layout.
- Updated event routing to exclusively use string-based IDs (Triple-ID pattern).
- Hardened 'ae_EventSession' type definitions to handle null values from V3 API/Dexie.

src/routes/events/[event_id]/(badges)/badges/ae_comp__badge_search.svelte

@@ -144,7 +144,7 @@
                     placeholder="name, email"
                     id="badge_fulltext_search_qry_str"
                     bind:value={$events_loc.badges.fulltext_search_qry_str}
-                    suggest="off"
+                    autocomplete="off"
                     data-lpignore="true"
                     class="input text-lg font-mono grow transition-all"
                     onkeyup={(e) => {