feat(auth): expose current session

[swkeever]

Summary

• add auth.get_session() for the immutable locally held session
• bind SDK-AUTH-002 to the canonical cross-language contract
• document local-only semantics and add strict unit/type/package coverage

Scope

This slice only reads current in-memory session state. It does not adopt, clear, revoke, persist, refresh, emit events, handle redirects or OAuth, manage identities or sessions, or add realtime behavior.

Verification

• uv run python scripts/check_openapi.py
• uv run ruff check .
• uv run ruff format --check .
• uv run mypy
• uv run pyright
• uv run pytest tests/unit -q
• contract dry-run with private fixture
• uv run python -m build
• git diff --check

[swkeever]

@codex review

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-29T01:35:56.710976Z	62609af	Manual request

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[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. More of your lovely PRs please.

Reviewed commit: 62609affbf

ℹ️ About Codex in GitHub

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• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".