Support using Aspire MCP with non-local clients

MCP servers are primarly used by local AI clients. For example, local clients such as VS Code or Claude Code are configured to talk to the local MCP server. Authentication in this situation is most commonly either unauthenticated, or using a HTTP header.

Non local clients, such as chatgpt.com, can also be configured to use MCP tools. Authentication options are different depending on the tool, but unauthenticated and OAuth are common.

Challenges with using Aspire MCP from an online client:

- Local Aspire MCP server must be addressable by the online client. The online client isn't running on localhost and can't call localhost on users machine. Could use devtunnels to expose local dashboard
- Local Aspire MCP server should be protected with OAuth. The dashboard could be its own OAuth server.