feat: FIT-1492: Increase interactive area of Data Manager column separators

[ricardoantoniocm]

This pull request makes improvements to the user interface for table column resizing and drag-and-drop interactions. The most important changes are grouped below by theme.

https://www.loom.com/share/23a1f86f75f24151b52eae6e3ebc904a

Resizer usability and styling improvements:

• Added a new CSS variable --handle-interactive-size to increase the interactive area for the resizer handle, making it easier for users to grab and resize columns. (Resizer.scss)
• Updated the .resizer__handle selector to use spacing variables for top and bottom positioning, set the handle width to --handle-interactive-size, and added a pseudo-element for improved visual feedback and easier hover state styling. (Resizer.scss)
• Enhanced hover and resizing states by animating the handle width and border color, providing clearer feedback during interaction. (Resizer.scss)

Table drag-and-drop interaction:

• Changed the cursor style for draggable table headers from move to grab, making the drag-and-drop interaction more intuitive for users. (TableHead.scss)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.62%. Comparing base (6b65387) to head (b8b9b8c).
⚠️ Report is 2 commits behind head on develop.

❗ There is a different number of reports uploaded between BASE (6b65387) and HEAD (b8b9b8c). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (6b65387)	HEAD (b8b9b8c)
pytests	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #9542      +/-   ##
===========================================
- Coverage    68.29%   60.62%   -7.67%     
===========================================
  Files         1163      885     -278     
  Lines        69098    43820   -25278     
  Branches     11813    11813              
===========================================
- Hits         47191    26567   -20624     
+ Misses       21900    17246    -4654     
  Partials         7        7              

Flag	Coverage Δ
lsf-integration	52.88% <ø> (-0.01%)	⬇️
lsf-unit	44.08% <ø> (ø)
pytests	?

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