🔒 Fix potential XSS via innerHTML in popup.js

[Labreo]

🎯 What: Replaced innerHTML usage in popup.js with standard SVG DOM construction (document.createElementNS) and replaceChildren() for container clearing.

⚠️ Risk: Rendering SVG content or clearing containers using innerHTML can introduce Cross-Site Scripting (XSS) vectors if dynamic strings or non-sanitized content are ever combined with HTML parsing.

🛡️ Solution:

1. Dynamically constructs the SVG icon element and child SVG line elements using document.createElementNS("http://www.w3.org/2000/svg", ...), avoiding HTML string parsing entirely.
2. Uses container.replaceChildren() instead of container.innerHTML = '' to clear list containers safely and idiomatically.

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PR created automatically by Jules for task 7906803126901353929 started by @Labreo

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