Fix cyclic thenable detection for multi-node cycles (#35368)

[parisaghm]

Summary

This change improves cyclic thenable detection in ReactFlightReplyServer by tracking visited ReactPromise instances during traversal.

Previously, the logic only detected direct self-references and relied on a fixed iteration limit to bail out. This meant multi-node cycles (e.g. A → B → C → A or A → B → C → B) were not detected immediately.

The updated implementation introduces a Set to record visited promises and rejects as soon as a previously seen ReactPromise is encountered, ensuring correct and early detection of all cyclic cases. A safety iteration counter is kept as a secondary defense, although it should not be reached under normal conditions.

Fixes #35368

How did you test this change?

• Manually reproduced the issue by constructing chains of ReactPromise instances forming different cycle patterns:
  • Direct self-reference (A → A)
  • Multi-node cycles (A → B → C → A)
  • Non-head cycles (A → B → C → B)
• Verified that the traversal now rejects immediately upon revisiting a previously seen ReactPromise, instead of iterating until the iteration limit.
• Confirmed that non-cyclic chains resolve normally once a non-ReactPromise or non-INITIALIZED value is reached.

Not run via full test suite (change is localized and verified through targeted reproduction).

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[unstubbable]

resolved in #35369