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>

werkout-frontend/next.config.mjs

@@ -0,0 +1,28 @@
+/** @type {import('next').NextConfig} */
+// v2
+const nextConfig = {
+  images: {
+    remotePatterns: [
+      {
+        protocol: "http",
+        hostname: "localhost",
+        port: "8000",
+      },
+      {
+        protocol: "http",
+        hostname: "0.0.0.0",
+        port: "8000",
+      },
+    ],
+  },
+  async rewrites() {
+    return [
+      {
+        source: "/media/:path*",
+        destination: "http://localhost:8000/media/:path*",
+      },
+    ];
+  },
+};
+
+export default nextConfig;