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/actions/buttjob.json

@@ -2,16 +2,16 @@
   "action_id": "buttjob",
   "action_name": "Buttjob",
   "action": {
-    "full_body": "bent over, back turned to viewer, kneeling or standing",
-    "head": "looking back over shoulder",
-    "eyes": "looking at viewer, half-closed",
-    "arms": "supporting upper body weight on cool surface or knees",
-    "hands": "resting on bed, knees or holding buttocks apart",
-    "torso": "arched back, leaning forward",
-    "pelvis": "pushed backward, hips elevated high",
-    "legs": "kneeling with thighs spread or standing bent",
-    "feet": "arched or plantar flexion",
-    "additional": "glutes pressed together, friction focus, skin indentation"
+    "full_body": "bent over, buttjob",
+    "head": "",
+    "eyes": "",
+    "arms": "",
+    "hands": "",
+    "torso": "",
+    "pelvis": "buttjob",
+    "legs": "",
+    "feet": "",
+    "additional": ""
   },
   "participants": {
     "solo_focus": "true",
@@ -26,12 +26,6 @@
   },
   "tags": [
     "buttjob",
-    "back to viewer",
-    "bent over",
-    "arched back",
-    "kneeling",
-    "ass focus",
-    "glutes",
-    "between buttocks"
+    "butt"
   ]
-}
+}