feat: add DXCC SAT award for satellite-only QSOs

Added new award "DXCC SAT" that only counts satellite QSOs (QSOs with
satName field set). This adds a new "satellite_only" key to award
definitions that filters to only include satellite communications.

Award definition:
- ID: dxcc-sat
- Name: DXCC SAT
- Target: 100 DXCC entities
- Only satellite QSOs count

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

src/backend/services/awards.service.js

@@ -22,6 +22,7 @@ function loadAwardDefinitions() {
   try {
     const files = [
       'dxcc.json',
+      'dxcc-sat.json',
       'was.json',
       'vucc-sat.json',
       'sat-rs44.json',
@@ -145,6 +146,12 @@ export async function calculateAwardProgress(userId, award, options = {}) {
     logger.debug('QSOs after allowed_bands filter', { count: finalQSOs.length });
   }
 
+  // Apply satellite_only filter if present
+  if (rules.satellite_only) {
+    finalQSOs = finalQSOs.filter(qso => qso.satName);
+    logger.debug('QSOs after satellite_only filter', { count: finalQSOs.length });
+  }
+
   // Calculate worked and confirmed entities
   const workedEntities = new Set();
   const confirmedEntities = new Set();
@@ -723,6 +730,11 @@ export async function getAwardEntityBreakdown(userId, awardId) {
     });
   }
 
+  // Apply satellite_only filter if present
+  if (rules.satellite_only) {
+    finalQSOs = finalQSOs.filter(qso => qso.satName);
+  }
+
   // Group by (entity, band, mode) slot for entity awards
   // This allows showing multiple QSOs per entity on different bands/modes
   const slotMap = new Map(); // Key: "entity/band/mode" -> slot object