feat: add escalation tool for ReAct Agent

[cotovanu-cristian]

What changed?

• add escalation tool support
• implement command based agent termination support via AgentGraphState

Development Package

• Add this package as a dependency in your pyproject.toml:

[project]
dependencies = [
  # Exact version:
  "uipath-langchain==0.1.21.dev1002401362",

  # Any version from PR
  "uipath-langchain>=0.1.21.dev1002400000,<0.1.21.dev1002410000"
]

[[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" }

[sgeorgescu-uipath]

This is no longer required and must be removed to not interfere with some LangGraph features.