perf: réduire crops VLM 80→30 + fix bridge learned workflows path

- 30 crops suffisent pour les éléments UI principaux
- ~6min/screenshot au lieu de 17min (3x plus rapide)
- Bridge cherche aussi dans live_sessions/workflows/

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

visual_workflow_builder/backend/services/learned_workflow_bridge.py

@@ -553,8 +553,14 @@ def list_learned_workflows_from_disk() -> List[Dict[str, Any]]:
 
     Retourne une liste de dicts avec les métadonnées de base.
     """
-    base_dir = Path(_ROOT) / "data" / "training" / "workflows"
-    if not base_dir.exists():
+    # Chercher dans les deux emplacements possibles
+    base_dirs = [
+        Path(_ROOT) / "data" / "training" / "workflows",
+        Path(_ROOT) / "data" / "training" / "live_sessions" / "workflows",
+    ]
+
+    existing_dirs = [d for d in base_dirs if d.exists()]
+    if not existing_dirs:
         return []
 
     workflows = []
@@ -578,13 +584,12 @@ def list_learned_workflows_from_disk() -> List[Dict[str, Any]]:
             except Exception as e:
                 logger.warning("Erreur lecture %s : %s", f, e)
 
-    # Racine
-    _scan_dir(base_dir)
-
-    # Sous-dossiers machine
-    for machine_dir in sorted(base_dir.iterdir()):
-        if machine_dir.is_dir():
-            _scan_dir(machine_dir, machine_id=machine_dir.name)
+    # Scanner tous les répertoires trouvés
+    for base_dir in existing_dirs:
+        _scan_dir(base_dir)
+        for machine_dir in sorted(base_dir.iterdir()):
+            if machine_dir.is_dir():
+                _scan_dir(machine_dir, machine_id=machine_dir.name)
 
     return workflows