fix: guard against empty ResizeObserver size arrays

[tran-simon]

Description of changes:

add optional chaining for contentBoxSize and borderBoxSize array.
prevents TypeError when contentBoxSize or borderBoxSize arrays are empty in certain browser implementations or edge cases.

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 98.40%. Comparing base (954d4ec) to head (3cfa380).

Files with missing lines	Patch %	Lines
.../internal/container-queries/use-resize-observer.ts	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #177      +/-   ##
==========================================
- Coverage   98.82%   98.40%   -0.43%     
==========================================
  Files          40       40              
  Lines         937      941       +4     
  Branches      263      255       -8     
==========================================
  Hits          926      926              
- Misses         11       15       +4     

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