feat: migrate experimental config loader documentation

- Add experimental section to documentation
- Migrate all config loader documentation from sdk-python
- Include comprehensive guides for:
  - Agent configuration loading
  - Tool configuration loading (including Agent-as-Tool)
  - Swarm configuration loading
  - Graph configuration loading
  - Structured output configuration
- Update navigation to include experimental features
- Maintain all original content and examples

Author: vawsgit

docs/experimental/README.md

@@ -0,0 +1,41 @@
+# Experimental Features
+
+## What are Experimental Features?
+
+Experimental features in Strands Agents are cutting-edge capabilities that are:
+- In active development and testing
+- Subject to breaking changes
+- Available for early feedback and evaluation
+- Not recommended for production use without careful consideration
+
+## Current Experimental Features
+
+### Configuration Loaders
+Declarative YAML-based configuration for agents, tools, swarms, and graphs.
+
+## Using Experimental Features
+
+### Installation
+```bash
+# Experimental features are included in the main SDK
+pip install strands-agents
+```
+
+### Enabling Experimental Features
+```python
+from strands.experimental.config_loader import AgentConfigLoader
+```
+
+## Stability and Support
+
+- **API Stability**: Experimental APIs may change between releases
+- **Documentation**: May be incomplete or subject to updates
+- **Support**: Community support through GitHub issues
+- **Migration**: Migration guides provided when features graduate to stable
+
+## Feedback and Contributions
+
+We encourage feedback on experimental features:
+- [GitHub Issues](https://github.com/strands-agents/sdk-python/issues)
+- [Discussions](https://github.com/strands-agents/sdk-python/discussions)
+- [Contributing Guide](https://github.com/strands-agents/sdk-python/blob/main/CONTRIBUTING.md)