🍱 frontend/assets: Add image generation script and assets for multiple projects

- Created script `generate_images.nu` to automate WebP/JPEG-XL conversions with low-res placeholders.
- Added new source image `data_hub_1.png`.
- Generated WebP and JPEG-XL assets for projects: carplexity, data_hub, endolingual, icons, parva, and tiles.
- Created both high-quality and low-resolution variants for all project assets.

crates/frontend/assets/generate_images.nu

@@ -0,0 +1,28 @@
+#!/usr/bin/env nu
+
+# Generate low-res placeholders and high-res WebP and JPEG-XL versions of images
+
+let images = (ls ...(glob *.{png,jpg,jpeg}) | get name)
+
+mkdir webp
+mkdir jxl
+
+for image in $images {
+    let base = ($image | path parse | get stem)
+    let ext = ($image | path parse | get extension)
+
+    print $"Generating high-res WebP for ($image)"
+    magick $image -quality 85 $"webp/($base).webp"
+
+    print $"Generating high-res JPEG-XL for ($image)"
+    magick $image -quality 85 $"jxl/($base).jxl"
+
+    # Resize to 300px width, quality 20
+    print $"Generating low-res placeholder for ($image)"
+    magick $image -resize 300 -quality 20 $"webp/($base)_low.webp"
+
+    print $"Generating low-res JPEG-XL placeholder for ($image)"
+    magick $image -resize 300 -quality 20 $"jxl/($base)_low.jxl"
+}
+
+print "Generation complete. Check crates/frontend/assets/webp and crates/frontend/assets/jxl for new files."