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/clothing/french_maid_02.json

@@ -2,7 +2,7 @@
   "outfit_id": "french_maid_02",
   "outfit_name": "French Maid (Latex)",
   "wardrobe": {
-    "full_body": "",
+    "full_body": "latex maid",
     "headwear": "hairband",
     "top": "corset, low cut top",
     "bottom": "frilled skirt",
@@ -22,4 +22,4 @@
     "French Maid",
     "latex"
   ]
-}
+}