Enhance README for Group Details plugin with detailed instructions on regenerating images.js. Added clarification on the build script functionality and emphasized the importance of committing both PNG assets and the generated images.js file after changes.

Author: KennyG

plugins/GroupDetails/README.md

@@ -71,18 +71,32 @@ The plugin picks a PNG badge using a 2% tolerance (`>= 98%` of target resolution
 
 ## Assets And Build
 
-Badges are authored as PNG files in `assets/` and embedded into `images.js` as base64 data URIs.
+Badges are authored as PNG files in `assets/` and embedded into `images.js` as base64 data URIs.  The image.js provides base64 data back to the plugin and users can ultimately swap a logo on their plugin for further customiation if desired.
+`images.js` is generated output and should not be hand-edited.
 
 - Source files: `plugins/GroupDetails/assets/*.png`
 - Generated file: `plugins/GroupDetails/images.js`
+- Build script: `plugins/GroupDetails/build.sh`
 
-Regenerate `images.js` after changing PNGs:
+### Regenerating `images.js`
+
+From `plugins/GroupDetails/`:
 
 ```bash
 bash build.sh
 ```
 
-`build.sh` reads `assets/*.png`, sorts filenames deterministically, and rewrites `images.js`.
+What `build.sh` does:
+
+- validates that `assets/` exists and contains at least one `*.png`
+- reads `assets/*.png`
+- sorts filenames deterministically (stable diffs)
+- rewrites `images.js` with `window.GroupDetailsImages = { ... }`
+
+Commit both:
+
+- the changed PNG files in `assets/`
+- the regenerated `images.js`
 
 ## Updates Not Showing?