feat: add product stock & measure unit; refactor & optimize product tenancy performance

[KilianTrunk]

No description provided.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 41.53005% with 107 lines in your changes missing coverage. Please review.
✅ Project coverage is 45.96%. Comparing base (f63fd30) to head (31766de).

Files with missing lines	Patch %	Lines
...nt/Resources/ProductResource/Pages/EditProduct.php	0.00%	103 Missing ⚠️
src/Filament/Resources/ProductResource.php	95.16%	3 Missing ⚠️
.../Resources/ProductResource/Pages/CreateProduct.php	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main      #35      +/-   ##
============================================
+ Coverage     38.40%   45.96%   +7.55%     
- Complexity     1426     1439      +13     
============================================
  Files           104      104              
  Lines          6669     6771     +102     
============================================
+ Hits           2561     3112     +551     
+ Misses         4108     3659     -449     

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[SlimDeluxe]

Need an update to v4