Support external MCP servers with SSE transport

Enable support for external MCP servers that only have an SSE remote available.

Previously, Gram could only support external MCP servers that used the Streamable HTTP transport. Now, servers that still use the deprecated SSE type will be transparently adapted to Streamable HTTP. MCP clients will still use Streamable HTTP to interact with the external MCP server via Gram:

CLIENT <-(Streamable HTTP)-> GRAM <-(SSE)-> EXTERNAL MCP SERVER

Features

• Adapt SSE external MCP servers to Streamable HTTP #1142  - Supports external MCP servers with SSE, enhancing compatibility. (Author: @walker-tx )

Bug fixes

• GitHub Action workflow for versioning packages #1171  - Corrects GitHub Action for consistent versioning. (Author: @adaam2 )
• Fix and split up Storybook stories #1177  - Improves Storybook integration for better testing flows. (Author: @adaam2 )
• Move away from hardcoded API URL #1175  - Increases flexibility by removing hardcoded API URLs. (Author: @disintegrator )