docs: document mode groups feature in CLAUDE.md and README.md

Add documentation for the new configurable mode groups feature:
- CLAUDE.md: Add modeGroups to Award Rule Options section
- CLAUDE.md: Update Award Detail View section with mode group info
- CLAUDE.md: Add to Recent Development Work (January 2026)
- README.md: Add GET /api/awards/:awardId endpoint
- README.md: Add new Mode Groups section in Features in Detail

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

README.md

@@ -258,6 +258,7 @@ The application will be available at:
 
 ### Awards
 - `GET /api/awards` - Get all available awards
+- `GET /api/awards/:awardId` - Get single award definition (includes mode groups)
 - `GET /api/awards/batch/progress` - Get progress for all awards (optimized, single request)
 - `GET /api/awards/:awardId/progress` - Get award progress for a specific award
 - `GET /api/awards/:awardId/entities` - Get entity breakdown
@@ -800,6 +801,26 @@ bun run db:studio
 
 ## Features in Detail
 
+### Mode Groups (Award Detail View)
+
+The award detail view includes configurable mode groups for filtering multiple modes together:
+
+**Available Mode Groups** (varies by award):
+- **Mixed Mode**: All modes aggregated by band (default view)
+- **Digi-Modes**: FT8, FT4, MFSK, PSK31, RTTY, JT65, JT9
+- **Classic Digi-Modes**: PSK31, RTTY, JT65, JT9 (excludes FT8, FT4, MFSK)
+- **Mixed-Mode w/o WSJT-Modes**: PSK31, RTTY, AM, SSB, FM, CW (excludes WSJT modes)
+- **Phone-Modes**: AM, SSB, FM
+- **Individual Modes**: CW, SSB, FT8, etc.
+
+The mode filter dropdown displays:
+1. Mixed Mode (default)
+2. Mode groups (configurable per award)
+3. Visual separator (`─────`)
+4. Individual modes
+
+Awards can define custom `modeGroups` in their JSON definition to add additional mode groupings.
+
 ### Background Job Queue
 
 The application uses an in-memory job queue system for async operations: