Fix test failures in PR #9190: Set.intersection and ResizeObserver compatibility

[Copilot]

PR #9190 replaces react-lazylog with @melloware/react-logviewer but fails tests due to ES2025 Set.intersection() usage and missing ResizeObserver in jsdom.

Changes

Replace Set.intersection() with compatible implementation (ui/helpers/filter.js)

• Set.prototype.intersection() unavailable in Node v20.20
• Manually count intersection size to replicate behavior:

// Before (ES2025)
new Set(arr1).intersection(new Set(arr2)).size === arr1.length

// After (compatible)
let intersectionSize = 0;
for (const item of set1) {
  if (set2.has(item)) intersectionSize++;
}
return intersectionSize === arr1.length;

Add ResizeObserver mock (tests/ui/test-setup.js)

• @melloware/react-logviewer requires ResizeObserver
• jsdom doesn't provide it; added minimal mock with constructor signature

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• circleci.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.09%. Comparing base (e675128) to head (98a3109).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #9191      +/-   ##
==========================================
+ Coverage   82.07%   82.09%   +0.01%     
==========================================
  Files         602      602              
  Lines       33794    33800       +6     
  Branches     3070     3069       -1     
==========================================
+ Hits        27737    27747      +10     
- Misses       5741     5927     +186     
+ Partials      316      126     -190     

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