MCP Management via Cmdlet

[theznerd]

Summary of the new feature / enhancement

As a user I want to be able to manage mcp.json using a standard set of commands rather than needing to manually edit the file.

Proposed technical implementation details (optional)

Creation of a set of commands to manage MCP servers in themcp.json file:

• Get-AIShellMCPServer: List out existing MCP servers. List all by default, or wildcard search by name.
• Add-AIShellMCPServer: Adds an MCP server to the list
• Remove-AIShellMCPServer: Removes an MCP server from the list by name
• Set-AIShellMCPServer: Change values in an existing MCP server

Sure there are other commands that could be listed, but this seems like a good start for the basics.

[theznerd]

Maybe these would be better served as enhancements to the /mcp command (#402) e.g.:

• /mcp list (already by default I guess with /mcp)
• /mcp add <name> [options]
• /mcp remove <name>
• /mcp set <name> [options]

Options list easily defined for type/command:

• --type <stdio|https>
• --command <command>

A bit more challenging with the argument list:

• /mcp set <name> --args add <argument>
• /mcp set <name> --args remove <argument>
• /mcp add <name> --type <stdio|https> --command <command> --arg <argument1> ... --arg <argument_n_>