chore(dgx): snapshot consolidation WIP pour transfert poc DGX

Regroupe le WIP non committé requis pour le clone/runtime DGX (Option A) :
- api_stream.py : préflight replay + smoke santé modèles + handler 403 WP-B
- de-hardcode VLM : vlm_config, gpu/*, vram_orchestrator, ollama_manager
- stream_processor, semantic_matcher, agent_chat (app/planner/intent)
- workflows.db (acquis ; le transfert artifacts le mettra à jour + rewrite chemins)
- docs : plans DGX, benchmarks VLM/grounders, recherche SOTA, coordination 8 juin

Snapshot destiné à la branche poc-dgx poussée sur Gitea pour cloner le DGX.
Scan anti-secret : clean. graphify (repo embarqué) exclu.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

core/gpu/ollama_manager.py

@@ -13,6 +13,8 @@ from typing import List, Optional
 
 import aiohttp
 
+from core.detection.vlm_config import get_reasoning_model
+
 logger = logging.getLogger(__name__)
 
 
@@ -32,7 +34,7 @@ class OllamaManager:
     def __init__(
         self,
         endpoint: str = "http://localhost:11434",
-        model: str = "gemma4:e4b",
+        model: Optional[str] = None,
         default_keep_alive: str = "5m"
     ):
         """
@@ -44,7 +46,7 @@ class OllamaManager:
             default_keep_alive: Default keep-alive duration
         """
         self._endpoint = endpoint.rstrip("/")
-        self._model = model
+        self._model = model or get_reasoning_model()
         self._default_keep_alive = default_keep_alive
         self._session: Optional[aiohttp.ClientSession] = None