Add AWS Bedrock provider documentation

- Created new documentation file for AWS Bedrock LLM provider
- Added AWS Bedrock to the navigation in docs.json under Advanced Configuration > LLM Configuration > Providers
- Documentation explains how to configure OpenHands to use AWS Bedrock models via OpenAI-compatible API endpoint
- Includes step-by-step instructions for setting up Custom Model, Base URL, and API Key

Co-authored-by: openhands <openhands@all-hands.dev>

Author: openhands-agent

docs.json

@@ -73,6 +73,7 @@
                       "group": "Providers",
                       "pages": [
                         "openhands/usage/llms/openhands-llms",
+                        "openhands/usage/llms/aws-bedrock",
                         "openhands/usage/llms/azure-llms",
                         "openhands/usage/llms/google-llms",
                         "openhands/usage/llms/groq",

openhands/usage/llms/aws-bedrock.mdx

@@ -0,0 +1,25 @@
+---
+title: AWS Bedrock
+description: OpenHands can work with AWS Bedrock models using an OpenAI-compatible API endpoint.
+---
+
+## Configuration
+
+AWS Bedrock provides OpenAI-compatible API endpoints for their models. You can find their documentation on using the OpenAI Chat Completions API [here](https://docs.aws.amazon.com/bedrock/latest/userguide/inference-chat-completions.html).
+
+To configure OpenHands to use AWS Bedrock:
+
+1. In the OpenHands UI, navigate to Settings under the `LLM` tab
+2. Enable `Advanced` options
+3. Set the following:
+   - `Custom Model` to `openai/{model_name}` (e.g. `openai/anthropic.claude-3-5-sonnet-20240620-v1:0`)
+   - `Base URL` to `https://bedrock-runtime.{region}.amazonaws.com/openai/v1` (e.g. `https://bedrock-runtime.us-west-2.amazonaws.com/openai/v1`)
+   - `API Key` to your AWS Bedrock API key
+
+<Note>
+The `openai/` prefix in the Custom Model field indicates that OpenHands should use an OpenAI-compatible API format. It does not mean you are directly calling the OpenAI provider.
+</Note>
+
+<Note>
+Replace `{region}` with your desired AWS region (e.g., `us-west-2`, `us-east-1`). Ensure the region you specify matches where your Bedrock models are available.
+</Note>