fix: round up label width in ER diagram for Safari

[shikaan]

📑 Summary

On Safari, subpixel gets rounded differently than in Chromium-based browsers, leading to issues like #6640 This change, rounds up the size of the labels and its containers to prevent the issue.

Resolves #6640

📏 Design Decisions

This just rounds up the size of the label. As far as I can tell, everything renders correctly - however I am not sure about downstream effects of this change and a thorough review would be appreciated.

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commit: ac902ce

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.

Project coverage is 3.87%. Comparing base (8a703bd) to head (ac902ce).

Files with missing lines	Patch %	Lines
...ndering-util/rendering-elements/shapes/drawRect.ts	0.00%	3 Missing ⚠️
...c/rendering-util/rendering-elements/shapes/util.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           develop   #6641      +/-   ##
==========================================
- Coverage     3.87%   3.87%   -0.01%     
==========================================
  Files          413     414       +1     
  Lines        43292   43304      +12     
  Branches       666     666              
==========================================
  Hits          1679    1679              
- Misses       41613   41625      +12     

Flag	Coverage Δ
unit	3.87% <0.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...c/rendering-util/rendering-elements/shapes/util.ts	0.00% <0.00%> (ø)
...ndering-util/rendering-elements/shapes/drawRect.ts	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes

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Build	Status	Details	Updated (UTC)
default (Inspect)	⚠️ Changes detected (Review)	947 changed	Jun 9, 2025, 5:38 PM

[shikaan]

@ashishjain0512 @shubhamparikh2704 👋 Did you get a chance to review this change?
I can close/rework this PR if it's not going in the right direction.