Fix vision pipeline: ffmpeg removal by autoremove, increase vision timeout, reduce frame count, add Discord activity awareness

- bot/Dockerfile: Add ffmpeg to reinstall line after apt-get autoremove
  (autoremove was sweeping up ffmpeg as 'no longer needed' after playwright install)
- bot/utils/image_handling.py: Increase video analysis timeout 120s→300s, 6→3 for Tenor GIFs (GTX 1660 VRAM constraint)
- bot/utils/activities.py: Add _activity_changed_at timestamp tracking,
  get_current_activity_label() and get_current_activity_fresh() with 30-min decay
- bot/utils/cat_client.py: Pass current Discord activity to Cheshire Cat pipeline
- bot/utils/llm.py: Inject current Discord activity into system prompt
- cat-plugins/*: Forward Discord activity through working_memory to personality plugins
- bot/persona/*/preamble.txt: Add Discord status usage guidelines for character prompts
- llama-swap-rocm-config.yaml: Add qwen3.5 model entry for ComfyUI prompt generation
- AGENTS.md: New project documentation file

llama-swap-rocm-config.yaml

@@ -38,6 +38,15 @@ models:
       - japanese
       - japanese-model
 
+  # Qwen3.5 for ComfyUI prompt generation
+  qwen3.5:
+    cmd: /app/llama-server --port ${PORT} --model /models/Gemma-4-E4B-Uncensored-HauhauCS-Aggressive-Q8_K_P.gguf -ngl 99 -c 8192 --host 0.0.0.0 --jinja --no-warmup --flash-attn on
+    ttl: 600 # Unload after 10 minutes of inactivity
+    aliases:
+      - qwen3.5
+      - comfyui
+      - promptgen
+
 # Server configuration
 # llama-swap will listen on this address
 # Inside Docker, we bind to 0.0.0.0 to allow bot container to connect