FOUR-25084: Fix sidebar SVG icons so they inherit nav text color

[eiresendez]

Issue & Reproduction Steps

Sidebar menu SVG icons (base64 images) were rendering white instead of inheriting the nav text color.
Reproduce:

1. Open the sidebar with any item using a custom SVG icon and customized UI.
2. Note that font-awesome icons render red ($light), but SVG icons render white.

Solution

• Swapped tags for base64 SVGs to elements using CSS masks so icons use currentColor.
• Added .nav-icon.custom-icon styles to size the masked icons and inherit the nav link color in resources/sass/sidebar/sidebar.scss.
• Kept existing font-awesome behavior unchanged.

How to Test

1. Rebuild assets if needed (npm run dev or npm run build).
2. Open the sidebar; confirm custom SVG icons now display in the same red as font-awesome icons in both expanded and collapsed states.
3. Verify hover/active states still behave as before.

Related Tickets & Packages

• FOUR-25084

ci:deploy

Code Review Checklist

• I have pulled this code locally and tested it on my instance, along with any associated packages.
• This code adheres to ProcessMaker Coding Guidelines.
• This code includes a unit test or an E2E test that tests its functionality, or is covered by an existing test.
• This solution fixes the bug reported in the original ticket.
• This solution does not alter the expected output of a component in a way that would break existing Processes.
• This solution does not implement any breaking changes that would invalidate documentation or cause existing Processes to fail.
• This solution has been tested with enterprise packages that rely on its functionality and does not introduce bugs in those packages.
• This code does not duplicate functionality that already exists in the framework or in ProcessMaker.
• This ticket conforms to the PRD associated with this part of ProcessMaker.

[vladyrichter]

QA server K8S was successfully deployed https://ci-1c2b68a4c8.engk8s.processmaker.net

[processmaker-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
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No data about Duplication

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