revert: remove LoTW sync type support (QSL/QSO delta/full)

This reverts commit 5b78935 which added:
- Sync type parameter (qsl_delta, qsl_full, qso_delta, qso_full)
- getLastLoTWQSODate() function
- Sync type dropdown on QSO page
- Job queue handling of sync types

Reason: LoTW doesn't provide DXCC entity data for unconfirmed QSOs,
which causes award calculation issues. Going back to QSL-only sync.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/backend/services/lotw.service.js

@@ -401,6 +401,11 @@ export async function getUserQSOs(userId, filters = {}, options = {}) {
       // Both confirmed: Confirmed by LoTW AND DCL
       conditions.push(eq(qsos.lotwQslRstatus, 'Y'));
       conditions.push(eq(qsos.dclQslRstatus, 'Y'));
+    } else if (filters.confirmationType === 'any') {
+      // Confirmed by at least 1 service: LoTW OR DCL
+      conditions.push(
+        sql`(${qsos.lotwQslRstatus} = 'Y' OR ${qsos.dclQslRstatus} = 'Y')`
+      );
     } else if (filters.confirmationType === 'none') {
       // Not confirmed: Not confirmed by LoTW AND not confirmed by DCL
       conditions.push(

src/frontend/src/routes/qsos/+page.svelte

@@ -577,6 +577,7 @@
 
       <select bind:value={filters.confirmationType} on:change={applyFilters} class="confirmation-filter">
         <option value="all">All QSOs</option>
+        <option value="any">Confirmed by at least 1 service</option>
         <option value="lotw">LoTW Only</option>
         <option value="dcl">DCL Only</option>
         <option value="both">Both Confirmed</option>