docs: streamable server sample (#595)

- add a simple streamable http server example with auth
- update readme: replace quickstart example from sse server to
streamable server
- add readme files for samples, simple-streamable-server, notebooks

closes #170 

## How Has This Been Tested?
knit and inspector

## Breaking Changes
NaN

## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update

## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [x] I have added or updated documentation as needed

.github/workflows/build.yml

@@ -180,6 +180,7 @@ jobs:
         sample:
           - kotlin-mcp-client
           - kotlin-mcp-server
+          - simple-streamable-server
           - weather-stdio-server
 
     name: "Build Sample: ${{ matrix.sample }}"

.github/workflows/samples.yml

@@ -29,6 +29,7 @@ jobs:
         sample:
           - kotlin-mcp-client
           - kotlin-mcp-server
+          - simple-streamable-server
           - weather-stdio-server
 
     name: Build Sample (${{ matrix.sample }})