Extend the MCP tool wrapper to work with stdio

[AnuradhaKaruppiah]

Description

Closes #304

This PR extends the MCP tool client usage via stdio using a format similar to cursor/claude-desktop i.e. by providing {tool_name, command, args, env}

class MCPToolConfig(FunctionBaseConfig, name="mcp_tool_wrapper"):
>>>>>>>>>>>>>>>>> SNIP >>>>>>>>>>>>>>
    mcp_tool_name: str = Field(description="The name of the tool served by the MCP Server that you want to use")
    client_type: str = Field(default="sse", description="The type of client to use ('sse' or 'stdio')")
    command: str | None = Field(default=None, description="The command to run for stdio mode (e.g. 'docker' or 'python')")
    args: list[str] | None = Field(default=None, description="Additional arguments for the stdio command")
    env: dict[str, str] | None = Field(default=None, description="Environment variables to set for the stdio process")
>>>>>>>>>>>>>>>>> SNIP >>>>>>>>>>>>>>

The MCP stdio_client connects to a server by spawning a process and communicating with it over stdin/stdout.

Note: MCP SSE client is the recommended way for accessing remote tools and remains the default. The MCP stdio client is available for rapid-development/easy prototyping.

A. Sample usage with github MCP service

1. CLI Sample:

aiq info mcp --client-type stdio --command docker --args "run -i --rm -e GITHUB_PERSONAL_ACCESS_TOKEN ghcr.io/github/github-mcp-server" --env "GITHUB_PERSONAL_ACCESS_TOKEN=your_github_token"

Sample Output:

GitHub MCP Server running on stdio
add_issue_comment
add_pull_request_review_comment
create_branch
create_issue
create_or_update_file
create_pull_request
create_pull_request_review
create_repository
>>>>>>>>>>>>>>>>>> SNIP >>>>>>>>>>>>>>>>>>>>>

B. Sample usage with datetime MCP service
0. Install mcp_server_time package in your venv:

uv pip install mcp-server-time

1. CLI Sample:

aiq info mcp --client-type stdio --command python --args "-m mcp_server_time --local-timezone=America/Los_Angeles"

Sample Output:

get_current_time
convert_time

2. Sample Client (new simple_calculator config file, config-mcp-date-stdio.yml) -

aiq run --config_file examples/simple_calculator/configs/config-mcp-date-stdio.yml --input "Is the product of 2 * 4 greater than the current hour of the day?" 

By Submitting this PR I confirm:

• I am familiar with the Contributing Guidelines.
• We require that all contributors "sign-off" on their commits. This certifies that the contribution is your original work, or you have rights to submit it under the same license, or a compatible license.
  • Any contribution which contains commits that are not Signed-Off will not be accepted.
• When the PR is ready for review, new or existing tests cover these changes.
• When the PR is ready for review, the documentation is up to date with these changes.

[Copilot]

Pull Request Overview

This PR extends the MCP tool wrapper to support stdio mode in addition to the existing SSE mode. Key changes include:

• Updating the MCPToolConfig schema and client builder to support stdio parameters (command, args, env).
• Refactoring the MCP client structure by introducing a base client and a dedicated MCPStdioClient.
• Enhancing CLI commands, tests, and documentation to demonstrate and verify the stdio mode usage.

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/aiq/tools/test_mcp.py	Added tests for both SSE and stdio client usage, and for the MCPBuilder functionality.
src/aiq/tool/mcp/mcp_tool.py	Updated configuration handling to support stdio mode with new parameters and validation.
src/aiq/tool/mcp/mcp_client.py	Refactored client architecture by introducing a base client and a dedicated MCPStdioClient, and updated MCPBuilder accordingly.
src/aiq/cli/commands/info/list_mcp.py	Enhanced CLI options to support stdio mode configuration including command, args, and environment variables.
examples/simple_calculator/src/aiq_simple_calculator/configs/config-mcp-date-stdio.yml	Added sample config demonstrating usage of MCP stdio mode.
docs/source/workflows/mcp/mcp-client.md	Updated documentation to include examples and explanation for both SSE and stdio mode configurations.

[mdemoret-nv]

Could improve design a bit now that we have two client types by removing MCPBuilder