Merge verified Odysseus fixes

src/image_model_ids.py

@@ -0,0 +1,42 @@
+"""Small helpers for recognizing image-generation model IDs."""
+
+from __future__ import annotations
+
+
+_IMAGE_MODEL_PREFIXES = (
+    "gpt-image",
+    "dall-e",
+    "chatgpt-image",
+    "hidream",
+    "qwen-image",
+    "z-image",
+    "flux",
+    "stable-diffusion",
+    "sdxl",
+    "boogu",
+    "krea-2",
+)
+
+
+def model_id_leaf(model_id: str) -> str:
+    """Return the provider-stripped model id leaf in lowercase."""
+    return str(model_id or "").strip().split("/")[-1].lower()
+
+
+def looks_like_image_generation_model(model_id: str) -> bool:
+    """Return True when a model id should use image generation routes.
+
+    API providers can namespace image models, e.g. ``openai/gpt-5-image``.
+    Classify by the leaf so mixed endpoints can expose chat and image models
+    without marking the whole endpoint as image-only.
+    """
+    mid = str(model_id or "").strip().lower()
+    leaf = model_id_leaf(mid)
+    if not leaf:
+        return False
+    if any(leaf.startswith(prefix) for prefix in _IMAGE_MODEL_PREFIXES):
+        return True
+    # Newer OpenAI image models use names like gpt-5-image instead of
+    # gpt-image-1. Keep this pattern provider-agnostic.
+    return leaf.startswith("gpt-") and "-image" in leaf
+