Result retrieval misses terminal events beyond the first history page

[rmcdaniel]

Customer outcome

WorkflowHandle.result() returns the real terminal result or failure for a completed workflow even when its run history spans several Server API pages.

Reproduction

During Server #237 long-history qualification, published Server 2.4.19 and published Python SDK 2.3.4 completed a workflow with 100 recorded side effects. Server reported completed and output 4950, but handle.result() returned None. The history endpoint's default first page had StartAccepted, WorkflowStarted, and 98 SideEffectRecorded events. Its WorkflowCompleted event was on the next page. Client.get_result() scans only the first page.

Acceptance

• Follow the Server's opaque history page token with bounded page size to find the terminal event without accumulating the full history in memory.
• Preserve terminal result decoding and typed failure behavior, including external payload references.
• Expose explicit history pagination to callers and document its page semantics.
• Test a terminal event on a later page and a malformed repeated token.
• Verify the fix against the published Server image with a candidate SDK, then release and verify the published Python package before closing.

Related qualification: durable-workflow/server#237.

[rmcdaniel]

The fix in PR #82 merged at 72f25a3cf651204904f9b31d7d7eba1c56ea6e25 after Python 3.10/3.11/3.12, lint, package, docs and integration checks passed. Candidate source returned the expected 550725 for a 1,092-event, two-page workflow against published Server 2.4.19; Server #237's draft evidence PR holds the raw result and generator.

Release PR #83 prepares 2.3.5. Keep this issue open until PyPI publishes that exact source and a fresh published-package run retrieves a terminal result beyond the first history page.

[rmcdaniel]

Verified delivery: Python SDK 2.3.5 is published on PyPI from tagged source 53e7ddd57c1a31aa4ec6ce4395e50d3018c409e9. The wheel SHA-256 is 1db40895ed81d6df44a6e62db3305fa6ec01fce41296acf2a0beafb17e6e685f; the sdist SHA-256 is 74b58368a00a3da71db4607ae1003f41fa6c931e2a74cab22aa91ccc23c1003d. The release workflow built, published and verified both files.

The exact PyPI 2.3.5 package, with no source override, ran against published Server 2.4.19 image index sha256:77a61a9f46ca9765ee86174b9a50dab1b9e810250caa9e3551b800457a81862a. A fresh workflow completed with 1,092 ordered events across two history pages, 13 activities, and the expected result 550725. WorkflowHandle.result() returned 550725. The reproducible generator, command and raw result are in Server PR #245.

The public Server image does not bundle the Python SDK, and no public source consumer had an exact 2.3.4 runtime pin to update. Acceptance is complete for the Python result pagination defect. Server #237 remains open for long-history limits and recovery qualification.