Always call resizeCanvas

[marcusmoore]

Description

This PR partially addresses an issue (#15530) with the signature pad on small screens.

Currently, rendering the signature pad on very small screens (less than 470px it seems like) has two issues:

• The lines are blurry
• The lines progressively appear further to the right of the cursor location the further right the line is drawn:
  

With this PR the lines are drawn accurately and more clear:

This is achieved by always calling the function that handles high DPI screens and also re-calling it when the screen is re-sized.

But, two things I've noticed is that manually re-sizing the window from large to small or opening/closing the sidebar still exhibit the previous behavior. I'm opening this PR as-is since I think the major problem is solved and I couldn't find an easy solution for the last two issues.

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The diff for this looks worse than it is. Showing No Whitespace makes it a lot clearer since I removed an if block and de-indented a chunk of code.

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This builds on the work in #14577

Fixes #15530

Type of change

• Bug fix (non-breaking change which fixes an issue)

[what-the-diff]

PR Summary

• Initialization of SignaturePad: We've positioned the initialization of signaturePad at the beginning of the script. This leads to more efficient setup and use of this section of the application.
• Enhancements to the Resize Function: We've refined the explanatory comments within the resize function, even providing a URL for further insights into handling high DPI (dots per inch) scenarios. This improves understanding of how the function handles differently sized screens.
• Inclusion of SignaturePad Clear Function: We're now employing the signaturePad.clear() method within the resizeCanvas function. This guarantees accurate operation whenever the screen size alters, avoiding any potential inconsistencies.
• Minor Revisions in Comments: A few comments have been reworded to give clearer understanding, particularly around matters connected to mobile and DPI concerns. These changes make the script more comprehensible and easier to maintain.