Initial commit: OpenRouter Python SDK

Auto-generated Python SDK for OpenRouter API, providing comprehensive client library with:
- Chat completions and streaming support
- Embeddings API
- Model and provider information
- API key management
- Analytics and usage tracking
- OAuth authentication flows
- Full type hints and error handling

docs/models/utils/retryconfig.md

@@ -0,0 +1,24 @@
+# RetryConfig
+
+Allows customizing the default retry configuration. Only usable with methods that mention they support retries.
+
+## Fields
+
+| Name                      | Type                                | Description                             | Example   |
+| ------------------------- | ----------------------------------- | --------------------------------------- | --------- |
+| `strategy`                | `*str*`                             | The retry strategy to use.              | `backoff` |
+| `backoff`                 | [BackoffStrategy](#backoffstrategy) | Configuration for the backoff strategy. |           |
+| `retry_connection_errors` | `*bool*`                            | Whether to retry on connection errors.  | `true`    |
+
+## BackoffStrategy
+
+The backoff strategy allows retrying a request with an exponential backoff between each retry.
+
+### Fields
+
+| Name               | Type      | Description                               | Example  |
+| ------------------ | --------- | ----------------------------------------- | -------- |
+| `initial_interval` | `*int*`   | The initial interval in milliseconds.     | `500`    |
+| `max_interval`     | `*int*`   | The maximum interval in milliseconds.     | `60000`  |
+| `exponent`         | `*float*` | The exponent to use for the backoff.      | `1.5`    |
+| `max_elapsed_time` | `*int*`   | The maximum elapsed time in milliseconds. | `300000` |