[Docs] Reduce custom syntax used in docs (#27009)

Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

docs/design/arch_overview.md

@@ -49,7 +49,7 @@ Here is a sample of `LLM` class usage:
 
 More API details can be found in the [Offline Inference](#offline-inference-api) section of the API docs.
 
-The code for the `LLM` class can be found in <gh-file:vllm/entrypoints/llm.py>.
+The code for the `LLM` class can be found in [vllm/entrypoints/llm.py](../../vllm/entrypoints/llm.py).
 
 ### OpenAI-Compatible API Server
 
@@ -60,7 +60,7 @@ This server can be started using the `vllm serve` command.
 vllm serve <model>
 ```
 
-The code for the `vllm` CLI can be found in <gh-file:vllm/entrypoints/cli/main.py>.
+The code for the `vllm` CLI can be found in [vllm/entrypoints/cli/main.py](../../vllm/entrypoints/cli/main.py).
 
 Sometimes you may see the API server entrypoint used directly instead of via the
 `vllm` CLI command. For example:
@@ -74,7 +74,7 @@ python -m vllm.entrypoints.openai.api_server --model <model>
     `python -m vllm.entrypoints.openai.api_server` is deprecated
     and may become unsupported in a future release.
 
-That code can be found in <gh-file:vllm/entrypoints/openai/api_server.py>.
+That code can be found in [vllm/entrypoints/openai/api_server.py](../../vllm/entrypoints/openai/api_server.py).
 
 More details on the API server can be found in the [OpenAI-Compatible Server](../serving/openai_compatible_server.md) document.
 
@@ -101,7 +101,7 @@ processing.
 - **Output Processing**: Processes the outputs generated by the model, decoding the
   token IDs from a language model into human-readable text.
 
-The code for `LLMEngine` can be found in <gh-file:vllm/engine/llm_engine.py>.
+The code for `LLMEngine` can be found in [vllm/engine/llm_engine.py](../../vllm/engine/llm_engine.py).
 
 ### AsyncLLMEngine
 
@@ -111,9 +111,9 @@ incoming requests. The `AsyncLLMEngine` is designed for online serving, where it
 can handle multiple concurrent requests and stream outputs to clients.
 
 The OpenAI-compatible API server uses the `AsyncLLMEngine`. There is also a demo
-API server that serves as a simpler example in <gh-file:vllm/entrypoints/api_server.py>.
+API server that serves as a simpler example in [vllm/entrypoints/api_server.py](../../vllm/entrypoints/api_server.py).
 
-The code for `AsyncLLMEngine` can be found in <gh-file:vllm/engine/async_llm_engine.py>.
+The code for `AsyncLLMEngine` can be found in [vllm/engine/async_llm_engine.py](../../vllm/engine/async_llm_engine.py).
 
 ## Worker