[Story] Add and support a new "MCP" node

[epamLDadayan]

User Story 2: Add a New Node - MCP

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Description:

As a user, I want to use an MCP Node in my Pipeline to select and utilize individual tools from added MCPs. This node should have similar functionality and appearance as the Function Node, while supporting input/output states, input mappings, and interrupt configurations for the selected MCP tool.

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Acceptance Criteria:

1. Node Design and Appearance:

• The MCP Node must resemble the Function Node in design and layout. It should also have a MCP Node-specific color.

2. MCP and Tool Selection:

• The Toolkit Dropdown List in the node allows users to select only MCPs added to the Pipeline.
• Once an MCP is selected, its tools become available in the Tool Dropdown List for selection.
• Only one MCP and one Tool can be selected per MCP Node.
• Users can select/unselect both MCP and Tool from their respective dropdown lists.

3. MCP Node Scope:

• The MCP Node must only support added MCPs. It does not support Toolkits, Agents, or Pipelines.

4. Compatibility with LLM Node:

• MCPs must still be available for selection from the LLM Node, even when introduced in the MCP Node.

5. States (Input/Output):

• The MCP Node must support Input and Output fields for states.
• States must reflect the input/output requirements of the selected MCP Tool.

6. Interrupt Settings:

• The MCP Node must support:
  • Interrupt After: Stops execution if triggered after a certain step.
  • Interrupt Before: Stops execution if triggered before a certain step.

7. General Accessibility:

• The MCP Node must become available as soon as the MCP is added to the Pipeline.

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Notes for Developers and QA:

1. Ensure the Toolkit Dropdown List only displays MCPs already added to the Pipeline, and only their tools are visible in the Tool Dropdown List.
2. Validate input and output connections to ensure seamless integration of the MCP Node with other pipeline nodes.
3. Ensure all mappings and configurations are saved automatically when the Pipeline is saved.
4. Test edge cases for unselection of MCP/Tool and ensure the states/mappings reset correctly.

[HawkQing1]

@epamLDadayan it should be available on dev.