[FEATURE]: manage notebook migration at the cell level rather than the notebook level

[ericvergnaud]

Is there an existing issue for this?

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Problem statement

The current implementation skips notebooks for which the default language is not yet supported (Scala, R).
This is sub-optimal because these notebooks may contain cells that we can migrate: Python, SQL and %run

Proposed Solution

Enhance NotebookMigrator such that it only skips unsupported cells, rather than entire notebooks.

Additional Context

No response