[WIP] Fix failing GitHub Actions job Test Go Code on macos (#957)

* Initial plan

* Fix TOCTOU race in StateManager.getOrCreateScope

Co-authored-by: qmuntal <3747816+qmuntal@users.noreply.github.com>

* Add fast-path Get before atomic LoadOrStore in getOrCreateScope

Co-authored-by: qmuntal <3747816+qmuntal@users.noreply.github.com>

* Make HashMap.LoadOrStore lazily construct the value via a function

Co-authored-by: qmuntal <3747816+qmuntal@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: qmuntal <3747816+qmuntal@users.noreply.github.com>