Enable advertising unused capabilities

[SamMorrowDrums]

Servers advertise that they have a capability only if the corresponding feature was added. For example, a server will advertise the "prompts" capability only if AddPrompt was called before the client and server exchange initialization messages.

The above is from release notes, and is fine for static servers (the most common case), however servers that support the various dynamic features of MCP (such as the GitHub MCP Server) can do things like add the first Prompt after the initialisation call.

This means that implicit feature enablement is fine, but the ability to manually enable features that can become available is also a requirement to support the dynamic features of the MCP spec properly.

[jba]

Thanks, I was wondering if that use case was a real one. We'll add this ability. Perhaps Has{Prompts,Resources,Tools} booleans in ServerOptions?