[FEATURE]: opencode cli can list tools available through connected mcp server

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Describe the enhancement you want to request

As i was connecting opencode to a LiteLLM instance i noticed, that the status of the connection is visible via opencode cli through various methods such as opencode mcp auth list, opencode mcp debug <name> and opencode mcp auth <name>. But, when testing which tools the connected MCP exposes, i always needed to start a chat session and ask for it which was inconsistent and tedious. I missed a simple CLI command.
Therefore i want to add a opencode mcp tools <name> command (or similar) which connects to the configured mcp server and lists its tools. These tools are displayed in a similar way as currently opencode mcp auth list.