tip: terminate WS streams on error events (#50854)

[kvnloo]

Tip leaf (fork-only) — CLEAN

Maps to work-order issue #160. Upstream origin anomalyco#50854 (not touched / not promoted).

What: Treat top-level error events as terminal so OpenAI Responses websocket streams stop on provider errors (e.g. rate_limit_exceeded).

Commit: 7104bb323d02caffc1e225318650bc6c4d3edd00
Origin tip SHA: 583811a7b456790262501f510d1e9d72194071cc

Proof: fail→pass on packages/llm/test/provider/openai-responses.test.ts filter terminates an OpenAI Responses stream on a top-level error event (GREEN 1 / NEG 1 fail / RESTORE 1).

github_writes_origin: 0. Codex promote parked.

[github-actions]

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[github-actions]

Hey! Your PR title tip: terminate WS streams on error events (#50854) doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

See CONTRIBUTING.md for details.

[kvnloo]

READY_UPSTREAM

Rechecked before promotion:

• upstream PR fix(llm): terminate websocket streams on errors anomalyco/opencode#50854 is open
• current upstream head exactly matches Grok's tested tip: 583811a7b456790262501f510d1e9d72194071cc
• no prior kvnloo validation comment is present
• fail → pass → restore evidence in this fork PR applies to that exact head

Use local gh/Hermes to post the validation note upstream; the ChatGPT GitHub App gets 403 on anomalyco/opencode. Do not open a duplicate PR.