Add StarDesk to the Special Sponsor table in the root README and all 11 localized READMEs, with the description translated per language, and to the sponsor wall on the website. The logo links to the promo URL in both places.

Along the way:

- Run Prettier over the README family, which had drifted out of format, so the sponsor edits are not buried in a whole-file reformat.
- Finish removing the ukey sponsor: #5217 cleaned only the root README and left the row in all 10 non-Bengali localized READMEs pointing at a deleted image, plus an unreferenced copy of that image under the website's docs assets.
- Give the sponsor table a fixed-width logo column. GitHub sizes table columns in proportion to their content and forces `max-width: 100%` onto images, so a long description was shrinking both logos to roughly a quarter of their intended size; an HTML table with a 182px first cell renders them at 150px from 480px-wide containers up.

The StarDesk logo is a transparent mark, so it takes the dark-mode inversion the sponsor wall already applies to SerpApi and needs no `sponsor-logo-raw` opt-out.