docs: update gallery showcase and preview assets

[humanbydefinition]

Summary

This pull request synchronizes the dev branch into main, updating the community gallery showcase with new ecosystem projects, refreshed preview assets, and refined titles and descriptions.

Changes

1. Gallery Showcase Updates

• Added new showcase entries for official ecosystem projects:
  • extension.textmode.art (Textmode Overlay browser extension)
  • create.textmode.art (visual drawing canvas)
  • export.textmode.art (on-device media converter)
• Updated the loopdroneloop gallery asset to use the local preview image (/gallery/loopdroneloop.png).
• Refined and standardized all gallery titles and descriptions for concise, consistent presentation across card layouts.

2. Gallery Preview Images

• Replaced and optimized high-resolution preview images (1682 x 982 PNG) in public/gallery/:
  • automata-textmode-art.png
  • create-textmode-art.png
  • editor-textmode-art.png
  • export-textmode-art.png
  • extension-textmode-art.png
  • flok-textmode.png
  • loopdroneloop.png
  • patchies-app.png
  • sunnexo-internet-exploder.png

Verification

• Validated JSON syntax for .vitepress/data/gallery.json.
• Verified VitePress production build completes without errors.
• Verified that all preview image assets and gallery routes resolve cleanly.