Fixes #

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1. PR title: Should follow the format: TYPE(SCOPE): DESCRIPTION

   • feat(langgraph): add multi-tenant support

• Allowed TYPE and SCOPE values: https://github.com/langchain-ai/langgraph/blob/main/.github/workflows/pr_lint.yml#L19-L43

2. PR description:

• Write 1-2 sentences summarizing the change.
• The Fixes #xx line at the top is required for external contributions — update the issue number and keep the keyword. This links your PR to the approved issue and auto-closes it on merge.
• If there are any breaking changes, please clearly describe them.
• If this PR depends on another PR being merged first, please include “Depends on #PR_NUMBER” in the description.

3. Run make format, make lint and make test from the root of the package(s) you’ve modified.

• We will not consider a PR unless these three are passing in CI.

4. How did you verify your code works?

Additional guidelines:

• All external PRs must link to an issue or discussion where a solution has been approved by a maintainer, and you must be assigned to that issue. PRs without prior approval will be closed.
• PRs should not touch more than one package unless absolutely necessary.
• Do not update the uv.lock files or add dependencies to pyproject.toml files (even optional ones) unless you have explicit permission to do so by a maintainer.