phsl / new-api

* Removed `size="middle"` and `centered` props from the column-selector
  `Modal` in `ChannelsTable.js` to match the visual style used in
  `LogsTable`.
* Re-added `size="middle"` to the main `Table` component to preserve the
  original table sizing.
* Ensures consistent UI/UX across both channel and log column settings
  modals.