Restore getModelSessionById usage broken by CV branch merge

[Creylay]

Summary

Fixes a runtime crash (getModelSessionById is not defined) when opening a run's results. An earlier refactor (ca699b142) removed the local getModelSessionById import/fetch from LiveMetricsChart in favor of the modelSessionDetail prop already fetched by the parent, but left a separate isCV check still calling the now-unimported function directly (and synchronously, even though it's async). This block now reuses modelSessionDetail instead of re-fetching the session.

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Type of Change

Check all that apply like this [x]:

• Backend change
• Frontend change
• CI / Workflow change
• Build / Packaging change
• Bug fix
• Documentation

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Changes (by file)

• DashAI/front/src/components/models/LiveMetricsChart.jsx: replaced the broken isCV useMemo (which called an unimported getModelSessionById synchronously) with a derivation from the already-available modelSessionDetail prop.

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Testing

• Manually verified: opening a run's results (both CV and non-CV sessions) no longer throws and the CV-specific view renders correctly.