Support pinning adapter via server args. (#9249)

docs/advanced_features/server_arguments.md

@@ -179,7 +179,7 @@ Please consult the documentation below and [server_args.py](https://github.com/s
 | `--enable-lora` | Enable LoRA support for the model. This argument is automatically set to True if `--lora-paths` is provided for backward compatibility. | False |
 | `--max-lora-rank` | The maximum LoRA rank that should be supported. If not specified, it will be automatically inferred from the adapters provided in `--lora-paths`. This argument is needed when you expect to dynamically load adapters of larger LoRA rank after server startup. | None |
 | `--lora-target-modules` | The union set of all target modules where LoRA should be applied (e.g., `q_proj`, `k_proj`, `gate_proj`). If not specified, it will be automatically inferred from the adapters provided in `--lora-paths`. This argument is needed when you expect to dynamically load adapters of different target modules after server startup. You can also set it to `all` to enable LoRA for all supported modules. However, enabling LoRA on additional modules introduces a minor performance overhead. If your application is performance-sensitive, we recommend only specifying the modules for which you plan to load adapters. | None |
-| `--lora-paths` | The list of LoRA adapters. You can provide a list of either path in str or renamed path in the format {name}={path}. | None |
+| `--lora-paths` | The list of LoRA adapters to load. Each adapter must be specified in one of the following formats: <PATH> | <NAME>=<PATH> | JSON with schema {"lora_name":str,"lora_path":str,"pinned":bool} | None |
 | `--max-loras-per-batch` | Maximum number of adapters for a running batch, include base-only request. | 8 |
 | `--max-loaded-loras` | If specified, it limits the maximum number of LoRA adapters loaded in CPU memory at a time. The value must be greater than or equal to `--max-loras-per-batch`. | None |
 | `--lora-backend` | Choose the kernel backend for multi-LoRA serving. | triton |