Http2 stream retry

[zopenb]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Based on the search results, I found several related PRs that address stream retry and recovery logic:

Potential Related PRs:

1. fix: retry truncated provider streams #39473 - fix: retry truncated provider streams - Directly addresses provider stream retry logic
2. fix(session): retry top-level stream request timeouts #40268 - fix(session): retry top-level stream request timeouts - Handles stream request timeout retries
3. fix(provider): recover stalled model streams #40010 - fix(provider): recover stalled model streams - Addresses stalled stream recovery
4. fix(session): retry HTTP 408 request timeouts #39413 - fix(session): retry HTTP 408 request timeouts - HTTP timeout retry handling
5. fix(opencode): apply default header timeout to all providers #40069 - fix(opencode): apply default header timeout to all providers - Related timeout handling
6. fix(opencode): make long-lived provider streams robust to silent SSE terminations #39970 - fix(opencode): make long-lived provider streams robust to silent SSE terminations - Stream robustness improvements

These PRs all address related concerns around stream handling, retry logic, and timeout management. PR #41390 (the current PR) should be reviewed against these to ensure there's no duplicate effort or conflicting approaches to HTTP/2 stream retry functionality.

[github-actions]

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