workout generator audit: rules engine, structure rules, split patterns, injury UX, metadata cleanup

- Add rules_engine.py with quantitative rules for all 8 workout types
- Add quality gate retry loop in generate_single_workout()
- Expand calibrate_structure_rules to all 120 combinations (8 types × 5 goals × 3 sections)
- Wire WeeklySplitPattern DB records into _pick_weekly_split()
- Enforce movement patterns from WorkoutStructureRule in exercise selection
- Add straight-set strength support (single main lift, 4-6 rounds)
- Add modality consistency check for duration-dominant workout types
- Add InjuryStep component to onboarding and preferences
- Add sibling exercise exclusion in regenerate and preview_day endpoints
- Display generator warnings on dashboard
- Expand fix_rep_durations, fix_exercise_flags, fix_movement_pattern_typo
- Add audit_exercise_data and check_rules_drift management commands
- Add Next.js frontend with dashboard, onboarding, preferences, history pages
- Add generator app with ML-powered workout generation pipeline
- 96 new tests across 7 test modules

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

exercise/models.py

@@ -1,12 +1,40 @@
 from django.db import models
 from django.conf import settings
+from django.core.validators import MinValueValidator, MaxValueValidator
 from random import randrange
 
+
+DIFFICULTY_CHOICES = [
+    ('beginner', 'Beginner'),
+    ('intermediate', 'Intermediate'),
+    ('advanced', 'Advanced'),
+]
+
+TIER_CHOICES = [
+    ('primary', 'Primary'),
+    ('secondary', 'Secondary'),
+    ('accessory', 'Accessory'),
+]
+
+IMPACT_CHOICES = [
+    ('none', 'None'),
+    ('low', 'Low'),
+    ('medium', 'Medium'),
+    ('high', 'High'),
+]
+
+STRETCH_POSITION_CHOICES = [
+    ('lengthened', 'Lengthened'),
+    ('mid', 'Mid-range'),
+    ('shortened', 'Shortened'),
+]
+
+
 # Create your models here.
 class Exercise(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
-    name = models.CharField(null=True, blank=True, max_length=512)
+    name = models.CharField(max_length=512, default='')
     description = models.CharField(null=True, blank=True, max_length=1024)
     side = models.CharField(null=True, blank=True, max_length=64)
     is_two_dumbbells = models.BooleanField(default=False)
@@ -24,26 +52,49 @@ class Exercise(models.Model):
     estimated_rep_duration = models.FloatField(null=True, blank=True, max_length=255)
     video_override = models.CharField(null=True, blank=True, max_length=255)
 
+    # New fields for workout generation quality
+    is_compound = models.BooleanField(default=False)
+    difficulty_level = models.CharField(
+        max_length=16, choices=DIFFICULTY_CHOICES, null=True, blank=True
+    )
+    exercise_tier = models.CharField(
+        max_length=16, choices=TIER_CHOICES, null=True, blank=True
+    )
+    complexity_rating = models.IntegerField(
+        null=True, blank=True,
+        validators=[MinValueValidator(1), MaxValueValidator(5)]
+    )
+    hr_elevation_rating = models.IntegerField(
+        null=True, blank=True,
+        validators=[MinValueValidator(1), MaxValueValidator(10)]
+    )
+    impact_level = models.CharField(
+        max_length=8, choices=IMPACT_CHOICES, null=True, blank=True
+    )
+    stretch_position = models.CharField(
+        max_length=16, choices=STRETCH_POSITION_CHOICES, null=True, blank=True
+    )
+    progression_of = models.ForeignKey(
+        'self', null=True, blank=True, on_delete=models.SET_NULL,
+        related_name='progressions'
+    )
+
     class Meta:
         ordering = ('name',)
 
     def __str__(self):
-        return self.name + " --------- " + self.description or "NA"
+        return (self.name or 'Unnamed') + " --------- " + (self.description or "NA")
     
     def video_url(self):
         if self.video_override is not None and len(self.video_override) > 0:
-            #return "/videos/hls_video?video_name="+self.video_override+".mp4&video_type=exercise_videos"
             return '/media/videos/'+ self.video_override +'_720p.m3u8'
-            # return "/media/exercise_videos/" + self.video_override
         else:
-            #return "/videos/hls_video?video_name="+self.name.replace(" ", "_")+".mp4&video_type=exercise_videos"
-            name = self.name.replace(" ", "_")
+            name = (self.name or '').replace(" ", "_")
             name = name.replace("'", "")
             return '/media/hls/'+ name + ".mp4" +'_720p.m3u8'
-            #return "/media/exercise_videos/" + self.name.replace(" ", "_") + ".mp4"
-    
+
     def audio_url(self):
-        return "/media/exercise_audio/" + self.name.replace(" ", "_") + ".m4a"
+        return "/media/exercise_audio/" + (self.name or '').replace(" ", "_") + ".m4a"
 
     def transition_url(self):
         return "/media/transitions_audio/" + self.name.replace(" ", "_") + ".m4a"