Create model_provider.md

Author: rm-openai

.github/ISSUE_TEMPLATE/model_provider.md

@@ -0,0 +1,26 @@
+---
+name: Custom model providers
+about: Questions or bugs about using non-OpenAI models
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+### Please read this first
+
+- **Have you read the custom model provider docs, including the 'Common issues' section?** [Model provider docs](https://openai.github.io/openai-agents-python/models/#using-other-llm-providers)
+- **Have you searched for related issues?** Others may have faced similar issues.
+
+### Describe the question
+A clear and concise description of what the question or bug is.
+
+### Debug information
+- Agents SDK version: (e.g. `v0.0.3`)
+- Python version (e.g. Python 3.10)
+
+### Repro steps
+Ideally provide a minimal python script that can be run to reproduce the issue.
+
+### Expected behavior
+A clear and concise description of what you expected to happen.