catalog: fill obvious publisher / license_spdx gaps

[TMHSDigital]

• publisher: pixabay-audio, pixabay-videos -> Pixabay; sky3d, terrain3d -> TokisanGames; ansimuz-sunnyland, ansimuz-industrial-parallax -> ansimuz. (The ~180 other blanks are single-entry publishers, which the rules allow.)
• license_spdx: charge-materials and blender-ellie-poses use a bare CC-BY; the sibling blender-studio-* entries are CC-BY-4.0. Confirm the version on the source page and set it.

The other ~68 missing license_spdx values are intentional (custom/varies/unknown/public-domain/bare GPL, as documented).

[TMHSDigital]

Both halves are settled. Publishers: pixabay-audio and pixabay-videos (Pixabay), sky3d and terrain3d (TokisanGames), ansimuz-sunnyland and ansimuz-industrial-parallax (ansimuz), merged in #49. license_spdx: left as is on purpose. Blender's demo-files card for the Ellie Pose Library says only "CC-BY" (read 2026-09-25), and charge-materials states no licence on its card, so recording a version would be a licence claim the source does not make. #50 independently reached the same conclusion.