fix: add allowCreateNew to filepicker

[grnd-alt]

resolves #1893
required for: nextcloud/server#54234

[codecov]

Codecov Report

❌ Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 45.85%. Comparing base (c277589) to head (af199ae).
⚠️ Report is 106 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/filepicker-builder.ts	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2070      +/-   ##
==========================================
- Coverage   46.38%   45.85%   -0.54%     
==========================================
  Files          15       15              
  Lines         429      434       +5     
  Branches       82       83       +1     
==========================================
  Hits          199      199              
- Misses        202      207       +5     
  Partials       28       28              

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[grnd-alt]

it feels like this default would be better off to be true but allowPickDirectory has a default of false and they maybe should be consistent?!

[susnux]

Maybe just use noMenu with default false

[susnux]

I think it would be good to call the pop noMenu with default false.
In the builder call it maybe setMenu or similar to disable it (so here the menu is also on by default).