Fix table component issues when rendering stub column values and hiding empty rows

[Maren-SSB]

The table component does not currently handle all table states correctly. The following issues have been identified:

Row header / stub column rendering

• The table component is not fully adapted to all possible values in the row header (stub column).
• This results in an unintended thick border being displayed at the top of the table.
• The component should render consistently regardless of the content or structure of row header values.

Empty table state when hiding empty rows

• The table component does not correctly handle cases where all rows are hidden when the "Hide empty rows" option is enabled.
• There is inconsistent behavior between desktop and mobile views when no rows remain in the table.
• The expected behavior for this scenario needs to be defined and implemented consistently across platforms.

[Maren-SSB]

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