Fix notebook plotly remount crash

[Creylay]

Summary

When two notebooks contained the same type of explorer (e.g. two correlation heatmaps) in the same list position, switching between notebooks (or deleting/reordering an item within a single notebook's explorer list) crashed the app with Uncaught runtime errors: Something went wrong with axis scaling inside Plotly's drawColorBar. Neither the notebook view nor its virtualized list gave React a stable identity per notebook/item, so React reused the same <Plot> DOM instance across structurally different figures instead of unmounting/remounting it. Plotly's incremental Plotly.react() update path can't safely patch a plot div's internal axis/colorbar state across genuinely different figures, which triggered the crash. Adding proper keys forces a clean remount whenever the underlying notebook or list item actually changes, so each figure always gets a fresh Plotly instance.

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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/notebooks/dataset/DatasetsCenterContent.jsx: added key={selectedNotebookId} to <NotebookVisualization> so switching notebooks fully remounts the notebook subtree (including all explorer plots) instead of reusing the previous notebook's component instances.
• DashAI/front/src/components/notebooks/notebook/NotebookView.jsx: added computeItemKey={(index, item) => \${item.type}-${item.id}`}to theVirtuoso` list so explorer/converter rows are identified by their actual id instead of by list position, preventing component/Plot reuse when items are deleted or reordered.

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Testing

• Created two notebooks with the same explorer type (same position in each list) and switched between them. No crash and each plot renders correctly.
• Within a single notebook, added two explorers of the same type with structurally different figures and deleted the first one to shift list positions.