Add "No models" message

[RHeckerIntel]

In huggingface import

When there are no models

In model list when there are no models:

In model list when there are models but search is used:

[codecov]

Codecov Report

Attention: Patch coverage is 22.22222% with 14 lines in your changes missing coverage. Please review.

Project coverage is 33.35%. Comparing base (762dd95) to head (fc31ffc).
Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/widgets/empty_model_widget.dart	6.66%	14 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #73      +/-   ##
==========================================
- Coverage   33.53%   33.35%   -0.19%     
==========================================
  Files          38       39       +1     
  Lines        1476     1493      +17     
==========================================
+ Hits          495      498       +3     
- Misses        981      995      +14     

Flag	Coverage Δ
unittests	33.35% <22.22%> (-0.19%)	⬇️

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