Function sanitizeFilename

sanitizeFilename(name: string, maxLen?: number): string
Sanitize a string for use in a filename.

Lowercases the input, strips non-alphanumeric characters (except spaces), collapses whitespace to single underscores, trims leading/trailing underscores, and truncates to maxLen characters.
Parameters
- name: string
  Raw title or label to sanitize.
- maxLen: number = 40
  Maximum length of the result (default 40).
Returns string
A filesystem-safe string, or an empty string if nothing remains.
Example
```
sanitizeFilename('My Awesome Note!!')   // 'my_awesome_note'
sanitizeFilename('  Piano Scales #3  ') // 'piano_scales_3'
```
- Defined in packages/utilities/src/filenames.ts:29