feat(loongsuite-instrumentation-langgraph): Add langgraph instrumentation to identify react agent

[Cirilla-zmh]

Description

Summary

This PR introduces OpenTelemetry instrumentation for LangGraph, enabling proper Agent and ReAct Step span creation when used together with the LangChain instrumentation.

Changes

New: LangGraph Instrumentation Package (loongsuite-instrumentation-langgraph)

• Patch create_react_agent to set _loongsuite_react_agent = True on CompiledStateGraph
• Patch Pregel.stream / Pregel.astream to inject metadata["_loongsuite_react_agent"] into RunnableConfig, so LangChain instrumentation can detect ReAct agents via callback metadata
• Use wrapt.wrap_function_wrapper (aligned with loongsuite-instrumentation-langchain)
• Add unit tests for the instrumentor, patches, and ReAct step spans

CI & Tooling

• Add loongsuite_lint_0.yml and loongsuite_test_0.yml workflows
• Add LangGraph instrumentation to tox-loongsuite.ini
• Add copilot-instructions.md

Fixes #136 (issue)

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Add unit tests

Does This PR Require a Core Repo Change?

• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[Copilot]

Pull request overview

Adds a new loongsuite-instrumentation-langgraph package that patches LangGraph’s ReAct agent entry points so LangChain instrumentation can correctly detect ReAct agents and emit Agent / ReAct Step spans.

Changes:

• Introduces a LangGraph instrumentor that wraps create_react_agent and Pregel.stream/astream to propagate ReAct detection metadata.
• Adds pytest coverage for patching behavior and ReAct-step span hierarchy.
• Extends tox and GitHub Actions workflows to lint/test the new instrumentation across supported Python versions.

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tox-loongsuite.ini	Adds tox envs/deps/commands for langgraph instrumentation tests + lint.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/test_react_step_spans.py	Integration-style tests validating Agent/Step/LLM span creation and parenting.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/test_patch.py	Unit tests for wrapper patching / unpatching behavior.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/test_instrumentor.py	Basic lifecycle/dependencies tests for the new instrumentor.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/requirements.oldest.txt	Oldest test dependency set for the new package.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/requirements.latest.txt	Latest test dependency set for the new package.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/conftest.py	Test fixtures wiring OTel providers + installing both instrumentors.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/tests/init.py	Test package marker (license header).
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/src/opentelemetry/instrumentation/langgraph/version.py	Introduces package version module.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/src/opentelemetry/instrumentation/langgraph/package.py	Declares _instruments metadata for the instrumentor.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/src/opentelemetry/instrumentation/langgraph/internal/patch.py	Implements wrapt wrappers for ReAct flagging + metadata injection.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/src/opentelemetry/instrumentation/langgraph/internal/init.py	Internal package marker (license header).
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/src/opentelemetry/instrumentation/langgraph/init.py	Implements LangGraphInstrumentor patch/unpatch logic.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/pyproject.toml	Defines new distribution metadata and OTel entry point.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/README.md	Documents installation, usage, and the patching data flow.
instrumentation-loongsuite/loongsuite-instrumentation-langgraph/CHANGELOG.md	Adds initial changelog entry for the new instrumentation.
copilot-instructions.md	Adds guidance around PLC0415 inline imports and naming conventions.
.github/workflows/loongsuite_test_0.yml	Adds CI matrix jobs for langgraph instrumentation tests.
.github/workflows/loongsuite_lint_0.yml	Adds CI job for langgraph instrumentation linting.

Comments suppressed due to low confidence (1)

instrumentation-loongsuite/loongsuite-instrumentation-langgraph/README.md:1

• The README shows calling instrument() and uninstrument() on two different LangGraphInstrumentor() instances. It’s safer and more idiomatic to use the same instance for both (especially if patch state becomes instance-scoped as suggested), e.g. create instrumentor = LangGraphInstrumentor() then call instrumentor.instrument() / instrumentor.uninstrument().

# LongSuite LangGraph Instrumentation

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