fix: Save & restore when leaving an edit page

[g123k]

Hi everyone!

The initial goal of this PR was to fix #6242.

But one more issue appeared, and this time for all SimpleInputWidget (labels, stores, origins…)
If you dismissed the popup to save or cancel, your current input was lost, and the item was not added to the list of values.
Now, if you dismiss this popup, the internal save is canceled and everything is restored.

ScreenRecording_01-20-2025.00-21-33_1.MP4

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 15 lines in your changes missing coverage. Please review.

Project coverage is 6.10%. Comparing base (4d9c7fc) to head (f9dbb31).
Report is 688 commits behind head on develop.

Files with missing lines	Patch %	Lines
...p/lib/pages/product/simple_input_page_helpers.dart	0.00%	8 Missing ⚠️
...mooth_app/lib/pages/product/simple_input_page.dart	0.00%	4 Missing ⚠️
..._app/lib/pages/product/add_basic_details_page.dart	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           develop   #6250      +/-   ##
==========================================
- Coverage     9.54%   6.10%   -3.45%     
==========================================
  Files          325     462     +137     
  Lines        16411   27113   +10702     
==========================================
+ Hits          1567    1656      +89     
- Misses       14844   25457   +10613     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.