Unraid deployment fixes and generator improvements

- Add Next.js rewrites to proxy API calls through same origin (fixes login/media on werkout.treytartt.com)
- Fix mediaUrl() in DayCard and ExerciseRow to use relative paths in production
- Add proxyTimeout for long-running workout generation endpoints
- Add CSRF trusted origin for treytartt.com
- Split docker-compose into production (Unraid) and dev configs
- Show display_name and descriptions on workout type cards
- Generator: rules engine improvements, movement enforcement, exercise selector updates
- Add new test files for rules drift, workout research generation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

generator/views.py

@@ -938,6 +938,16 @@ def preview_day(request):
 
     # Optional plan_id: exclude exercises from sibling workouts in the same plan (Item #9)
     plan_id = request.data.get('plan_id')
+    if plan_id in ('', None):
+        plan_id = None
+    elif not isinstance(plan_id, int):
+        try:
+            plan_id = int(plan_id)
+        except (TypeError, ValueError):
+            return Response(
+                {'error': 'plan_id must be an integer.'},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
 
     try:
         from generator.services.workout_generator import WorkoutGenerator
@@ -945,7 +955,7 @@ def preview_day(request):
         generator = WorkoutGenerator(preference)
 
         # If plan_id is provided, exclude sibling workout exercises
-        if plan_id:
+        if plan_id is not None:
             try:
                 plan = GeneratedWeeklyPlan.objects.get(
                     pk=plan_id,
@@ -974,6 +984,8 @@ def preview_day(request):
             workout_type=workout_type,
             scheduled_date=scheduled_date,
         )
+        if plan_id is not None:
+            day_preview['plan_id'] = plan_id
     except Exception as e:
         return Response(
             {'error': f'Day preview generation failed: {str(e)}'},