fix(computer_use): honor custom vision routing

tools/computer_use/vision_routing.py

@@ -28,6 +28,10 @@ Behaviour (mirrors ``vision_analyze`` for consistency)
   ``provider``, ``model``, or ``base_url`` non-empty / not ``"auto"``),
   the screenshot is routed through the aux vision pipeline. Users who
   pay for a dedicated vision model usually want it used.
+* Otherwise, if the user explicitly declared the active model vision-capable
+  via ``model.supports_vision`` / provider model config, return ``False``.
+  This is the escape hatch for custom/local OpenAI-compatible VLM routes that
+  are absent from models.dev and provider allowlists.
 * Otherwise, if the active main model+provider can carry an image inside
   a tool-result message AND the model reports ``supports_vision=True``
   in models.dev metadata, return ``False`` (use the multimodal path).
@@ -76,10 +80,52 @@ def _explicit_aux_vision_override(cfg: Optional[Dict[str, Any]]) -> bool:
     return True
 
 
-def _lookup_supports_vision(provider: str, model: str) -> Optional[bool]:
-    """Return models.dev ``supports_vision`` for *(provider, model)* or None."""
+def _lookup_user_declared_supports_vision(
+    provider: str,
+    model: str,
+    cfg: Optional[Dict[str, Any]],
+) -> Optional[bool]:
+    """Return config-declared ``supports_vision`` for the active route."""
+    try:
+        from agent.image_routing import _supports_vision_override
+    except Exception as exc:  # pragma: no cover - defensive
+        logger.debug(
+            "computer_use vision_routing: config override lookup import failed: %s",
+            exc,
+        )
+        return None
+    try:
+        return _supports_vision_override(cfg, provider, model)
+    except Exception as exc:  # pragma: no cover - defensive
+        logger.debug(
+            "computer_use vision_routing: config override lookup failed: %s",
+            exc,
+        )
+        return None
+
+
+def _lookup_supports_vision(
+    provider: str,
+    model: str,
+    cfg: Optional[Dict[str, Any]] = None,
+) -> Optional[bool]:
+    """Return config/models.dev ``supports_vision`` for *(provider, model)*."""
     if not provider or not model:
         return None
+    try:
+        from agent.image_routing import _lookup_supports_vision as _lookup_image_supports
+    except Exception:
+        _lookup_image_supports = None
+    if _lookup_image_supports is not None:
+        try:
+            return _lookup_image_supports(provider, model, cfg)
+        except Exception as exc:  # pragma: no cover - defensive
+            logger.debug(
+                "computer_use vision_routing: image-routing caps lookup failed "
+                "for %s:%s — %s",
+                provider, model, exc,
+            )
+            return None
     try:
         from agent.models_dev import get_model_capabilities
         caps = get_model_capabilities(provider, model)
@@ -137,11 +183,17 @@ def should_route_capture_to_aux_vision(
     if _explicit_aux_vision_override(cfg):
         return True
 
+    user_declared = _lookup_user_declared_supports_vision(provider, model, cfg)
+    if user_declared is True:
+        return False
+    if user_declared is False:
+        return True
+
     accepts_tool_image = _provider_accepts_multimodal_tool_result(provider, model)
     if accepts_tool_image is None or accepts_tool_image is False:
         return True
 
-    supports_vision = _lookup_supports_vision(provider, model)
+    supports_vision = _lookup_supports_vision(provider, model, cfg)
     if supports_vision is True:
         return False
     return True