Add extra prompts, endless generation, random character default, and small fixes

- Add extra positive/negative prompt textareas to all 9 detail pages with session persistence
- Add Endless generation button to all detail pages (continuous preview generation until stopped)
- Default character selector to "Random Character" on all secondary detail pages
- Fix queue clear endpoint (remove spurious auth check)
- Refactor app.py into routes/ and services/ modules
- Update CLAUDE.md with new architecture documentation
- Various data file updates and cleanup

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

data/styles/brushwork1llust.json

@@ -1,15 +1,15 @@
 {
-  "style_id": "brushwork1llust",
-  "style_name": "Brushwork",
-  "style": {
-    "artist_name": "",
-    "artistic_style": ""
-  },
   "lora": {
     "lora_name": "Illustrious/Styles/Brushwork1llust.safetensors",
+    "lora_triggers": "hshiArt",
     "lora_weight": 0.95,
-    "lora_triggers": "Brushwork1llust",
-    "lora_weight_min": 0.95,
-    "lora_weight_max": 0.95
-  }
+    "lora_weight_max": 0.9,
+    "lora_weight_min": 0.7
+  },
+  "style": {
+    "artist_name": "",
+    "artistic_style": "brushwork,layeredtextures,loose and expressive brushstrokes,bold and rough brushstrokes"
+  },
+  "style_id": "brushwork1llust",
+  "style_name": "Brushwork"
 }