Reduce bundle size

The bundle is ±160KB with comments and whitespaces.

The Google Closure Compiler is available in the Docker development container. Try any of these compilation level (although the `ADVANCED` level is most likely not possible for this project):

```
--compilation_level (-O) VAL : Specifies the compilation level to
use. Options: BUNDLE, WHITESPACE_ONLY,
SIMPLE (default), ADVANCED (default:
SIMPLE)
```

Start in the Docker development container and locate how the bundle is produced. Try the listed Google Closure Compiler compilation levels, beginning with BUNDLE, WHITESPACE_ONLY, or SIMPLE, and compare the resulting bundle size with the current roughly 160KB output. Done means producing a smaller bundle without breaking the project, though the issue gives no named test or target size.

Written by the indexing model from the issue text.