Add ComfyUI models documentation and download script

- Complete MODELS.md with detailed model descriptions
- Interactive download script for 5+ specialized SDXL models
- Updated README with model selection guide
- Fix docker-compose volumes path (/root/ComfyUI)
- API workflows for OpenWebUI integration

Models documented:
- RealVisXL (portraits)
- Juggernaut XL (versatile)
- DreamShaper (art/fantasy)
- SDXL Lightning (fast)
- Proteus (realism)

comfyui/docker-compose.yml

@@ -1,5 +1,6 @@
 # ComfyUI avec ROCm pour RX 7800 XT
 # Architecture: gfx1101 (Navi 32)
+# CORRIGÉ: utilise /root/ComfyUI (pas /home/user/ComfyUI)
 
 services:
   comfyui:
@@ -9,25 +10,25 @@ services:
     ports:
       - "8188:8188"
     volumes:
-      - ./models/checkpoints:/home/user/ComfyUI/models/checkpoints:Z
-      - ./models/vae:/home/user/ComfyUI/models/vae:Z
-      - ./models/loras:/home/user/ComfyUI/models/loras:Z
-      - ./output:/home/user/ComfyUI/output:Z
-      - ./input:/home/user/ComfyUI/input:Z
-      - ./custom_nodes:/home/user/ComfyUI/custom_nodes:Z
-      - ./workflows:/home/user/ComfyUI/workflows:Z
+      - ./models/checkpoints:/root/ComfyUI/models/checkpoints:Z
+      - ./models/vae:/root/ComfyUI/models/vae:Z
+      - ./models/loras:/root/ComfyUI/models/loras:Z
+      - ./output:/root/ComfyUI/output:Z
+      - ./input:/root/ComfyUI/input:Z
+      - ./custom_nodes:/root/ComfyUI/custom_nodes:Z
+      - ./workflows:/root/ComfyUI/workflows:Z
     devices:
       - /dev/kfd:/dev/kfd
       - /dev/dri:/dev/dri
     group_add:
       - video
-      - render
     environment:
       - HIP_VISIBLE_DEVICES=0
       - HSA_OVERRIDE_GFX_VERSION=11.0.1
       - PYTORCH_HIP_ALLOC_CONF=expandable_segments:True
       - COMFYUI_PORT=8188
       - COMFYUI_EXTRA_ARGS=--listen 0.0.0.0 --port 8188
+    privileged: true
     security_opt:
       - seccomp:unconfined
     cap_add:
@@ -35,13 +36,6 @@ services:
     shm_size: '8gb'
     stdin_open: true
     tty: true
-    deploy:
-      resources:
-        reservations:
-          devices:
-            - driver: amd
-              count: 1
-              capabilities: [gpu]
 
 networks:
   default: