fix(llm): drop nonexistent name from __all__

[BlueX888]

What does this PR fix?

livekit.agents.llm.__all__ listed RealtimeSessionRestoredEvent, but no such class exists anywhere in the package — realtime.py only defines RealtimeSessionReconnectedEvent. The dangling entry breaks the module's public import surface:

• from livekit.agents.llm import * fails immediately, because a star import resolves every __all__ name against the module: AttributeError: module 'livekit.agents.llm' has no attribute 'RealtimeSessionRestoredEvent' (the did-you-mean suggestion machinery has existed since Python 3.10, so all supported versions show it). A named import of the missing name instead raises ImportError: cannot import name ... on every Python version.
• from livekit.agents import llm followed by llm.RealtimeSessionRestoredEvent raises AttributeError at attribute-access time.

Any user code doing a star import of the module — or tooling that consumes __all__ to enumerate the public API (docs generation, stub builders, linters) — hits this on current main.

Root cause

The entry was born dangling: RealtimeSessionReconnectedEvent exists in realtime.py, but RealtimeSessionRestoredEvent never existed in any released version (verified against the published 1.1.0–1.8.8 wheels — the name appears only as this __all__ string), so the __all__ entry was most likely a typo'd or placeholder name for its sibling that no import ever validated. __all__ is a plain string list with no runtime check tying it to the module contents, so importing livekit.agents.llm itself still succeeds and nothing flagged the entry; it only surfaces when the name is actually resolved.

The fix

Remove the single stale "RealtimeSessionRestoredEvent" entry from __all__ in livekit-agents/livekit/agents/llm/__init__.py. It is the only entry without a backing attribute — all 78 other exports resolve. A repo-wide search confirms the name appears nowhere else; the only occurrence was the stale __all__ entry.

Testing

Adds tests/test_llm_exports.py:

• test_public_llm_exports_resolve — asserts every name in llm.__all__ is a real attribute of the module (mirrors the existing test_public_inference_exports_resolve in tests/test_inference_utils.py), so any future stale, removed, or renamed export is caught, not just this one.
• test_llm_star_import_resolves_every_export — executes from livekit.agents.llm import * and checks every __all__ name is bound.

Both tests fail on main at the stale entry:

AssertionError: llm.__all__ lists 'RealtimeSessionRestoredEvent', but livekit.agents.llm does not define it
AttributeError: module 'livekit.agents.llm' has no attribute 'RealtimeSessionRestoredEvent'. Did you mean: 'RealtimeSessionReconnectedEvent'?

and pass with this change. The surrounding llm unit tests (chat context, decisions, tools, fallback, cache breakpoints, inference utils, chat-item proto coverage, ...) still pass; the single failure in tests/test_duplex_adapter.py reproduces identically on main without this change and is unrelated.

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.

[davidzhao]

please remove the test file, it doesn't add any value

[BlueX888]

Thanks @davidzhao — done, the test file is removed. The branch is now just the one-line change dropping the nonexistent RealtimeSessionRestoredEvent from llm.__all__, and it is rebased onto current main. Every remaining __all__ entry resolves, from livekit.agents.llm import * works again, and the existing llm unit tests still pass.

[davidzhao]

thanks, lg