docs(readme): add logo, title, badges, links to other repos, standardize headings (strands-agents#102)

Author: awsarron

README.md

@@ -25,8 +25,10 @@
   <p>
     <a href="https://strandsagents.com/">Documentation</a>
     ◆ <a href="https://github.com/strands-agents/samples">Samples</a>
+    ◆ <a href="https://github.com/strands-agents/sdk-python">Python SDK</a>
     ◆ <a href="https://github.com/strands-agents/tools">Tools</a>
     ◆ <a href="https://github.com/strands-agents/agent-builder">Agent Builder</a>
+    ◆ <a href="https://github.com/strands-agents/mcp-server">MCP Server</a>
   </p>
 </div>
 
@@ -35,7 +37,7 @@ Strands Agents is a simple yet powerful SDK that takes a model-driven approach t
 ## Feature Overview
 
 - **Lightweight & Flexible**: Simple agent loop that just works and is fully customizable
-- **Model Agnostic**: Support for Amazon Bedrock, Anthropic, Llama, Ollama, and custom providers
+- **Model Agnostic**: Support for Amazon Bedrock, Anthropic, LiteLLM, Llama, Ollama, OpenAI, and custom providers
 - **Advanced Capabilities**: Multi-agent systems, autonomous agents, and streaming support
 - **Built-in MCP**: Native support for Model Context Protocol (MCP) servers, enabling access to thousands of pre-built tools
 
@@ -147,6 +149,7 @@ Built-in providers:
  - [LiteLLM](https://strandsagents.com/latest/user-guide/concepts/model-providers/litellm/)
  - [LlamaAPI](https://strandsagents.com/latest/user-guide/concepts/model-providers/llamaapi/)
  - [Ollama](https://strandsagents.com/latest/user-guide/concepts/model-providers/ollama/)
+ - [OpenAI](https://strandsagents.com/latest/user-guide/concepts/model-providers/openai/)
 
 Custom providers can be implemented using [Custom Providers](https://strandsagents.com/latest/user-guide/concepts/model-providers/custom_model_provider/)
 
@@ -174,9 +177,9 @@ For detailed guidance & examples, explore our documentation:
 - [API Reference](https://strandsagents.com/latest/api-reference/agent/)
 - [Production & Deployment Guide](https://strandsagents.com/latest/user-guide/deploy/operating-agents-in-production/)
 
-## Contributing
+## Contributing ❤️
 
-We welcome contributions! See our [Contributing Guide](https://github.com/strands-agents/sdk-python/blob/main/CONTRIBUTING.md) for details on:
+We welcome contributions! See our [Contributing Guide](CONTRIBUTING.md) for details on:
 - Reporting bugs & features
 - Development setup
 - Contributing via Pull Requests
@@ -187,6 +190,10 @@ We welcome contributions! See our [Contributing Guide](https://github.com/strand
 
 This project is licensed under the Apache License 2.0 - see the [LICENSE](LICENSE) file for details.
 
+## Security
+
+See [CONTRIBUTING](CONTRIBUTING.md#security-issue-notifications) for more information.
+
 ## ⚠️ Preview Status
 
 Strands Agents is currently in public preview. During this period: