fix: pass argument properties to mcp tool

[radugheo]

AgentMcpTool.argument_properties was parsed from agent.json but never passed to the constructed tool, so MCP tools with Argument / Text Builder / Static input variants ran as if nothing was configured. The LLM filled those args itself.

This switches MCP tools to StructuredToolWithArgumentProperties so the existing StaticArgsHandler in llm_node picks them up. In schema and all modes, the same argumentProperties from agent.json are matched onto server-discovered tools by name.

Development Package

• Use uipath pack --nolock to get the latest dev build from this PR (requires version range).
• Add this package as a dependency in your pyproject.toml:

[project]
dependencies = [
  # Exact version:
  "uipath-langchain==0.10.17.dev1006874458",

  # Any version from PR
  "uipath-langchain>=0.10.17.dev1006870000,<0.10.17.dev1006880000"
]

[[tool.uv.index]]
name = "testpypi"
url = "https://test.pypi.org/simple/"
publish-url = "https://test.pypi.org/legacy/"
explicit = true

[tool.uv.sources]
uipath-langchain = { index = "testpypi" }

[tool.uv]
override-dependencies = [
    "uipath-langchain>=0.10.17.dev1006870000,<0.10.17.dev1006880000",
]