🔒 Fix XSS in Setlist Render

[julesklord]

🎯 What: The vulnerability fixed was an XSS issue where unescaped string properties and user data injections (like id, si, gClass) were directly set via innerHTML into DOM strings via renderSets, renderPool, and renderSaved functions.
⚠️ Risk: A malicious user could craft a customized JSON payload to inject scripts via parameters like genre, title, or artist. When these payloads are rendered in innerHTML or evaluated within inline event handlers (e.g. onclick="delSong(${x.id})"), arbitrary scripts can execute on the page.
🛡️ Solution: The fix resolves the vulnerability by comprehensively wrapping sensitive values injected into .innerHTML templates with the existing esc() function. This safely sanitizes attributes and prevents malicious string termination or execution. Additionally, tested to make sure no regressions exist.

---

PR created automatically by Jules for task 9757668297218248178 started by @julesklord

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.