test: add unit tests for VibeThinker models configuration

Add comprehensive tests to verify:
- Models exist in model_prices_and_context_window.json
- Required fields (provider, mode, tokens) are present
- Context window values are correct (32K)
- Provider consistency with other Featherless AI models

tests/test_litellm/test_vibethinker_models.py

@@ -0,0 +1,49 @@
+"""
+Test VibeThinker models configuration.
+"""
+import json
+import pytest
+
+
+def test_vibethinker_models_in_model_prices():
+    """Verify VibeThinker models are correctly configured in model_prices_and_context_window.json."""
+    with open("model_prices_and_context_window.json", "r") as f:
+        model_prices = json.load(f)
+    
+    models = [
+        "featherless_ai/WeiboAI/VibeThinker-1.5B",
+        "featherless_ai/WeiboAI/VibeThinker-3B",
+    ]
+    
+    for model in models:
+        assert model in model_prices, f"{model} not found in model_prices_and_context_window.json"
+        
+        config = model_prices[model]
+        
+        # Verify required fields
+        assert config["litellm_provider"] == "featherless_ai", f"{model}: wrong provider"
+        assert config["mode"] == "chat", f"{model}: wrong mode"
+        assert "max_tokens" in config, f"{model}: missing max_tokens"
+        assert "max_input_tokens" in config, f"{model}: missing max_input_tokens"
+        assert "max_output_tokens" in config, f"{model}: missing max_output_tokens"
+        
+        # Verify context window (Qwen base models have 32K context)
+        assert config["max_input_tokens"] == 32768, f"{model}: incorrect max_input_tokens"
+        assert config["max_tokens"] == 32768, f"{model}: incorrect max_tokens"
+
+
+def test_vibethinker_provider_consistency():
+    """Verify VibeThinker models use the same provider pattern as other Featherless AI models."""
+    with open("model_prices_and_context_window.json", "r") as f:
+        model_prices = json.load(f)
+    
+    # Get all featherless_ai models
+    featherless_models = {k: v for k, v in model_prices.items() if k.startswith("featherless_ai/")}
+    
+    # VibeThinker models should exist
+    assert "featherless_ai/WeiboAI/VibeThinker-1.5B" in featherless_models
+    assert "featherless_ai/WeiboAI/VibeThinker-3B" in featherless_models
+    
+    # All should have the same provider
+    for model, config in featherless_models.items():
+        assert config["litellm_provider"] == "featherless_ai", f"{model}: inconsistent provider"