fix pet again

[justschen]

fix #327587

The latest animation update introduced double-buffered image switching to avoid flicker between animations:

• Before: there was one visible . Assigning image.src was enough for the browser to display it. The load event only restarted the eye animation, so URL normalization could not prevent the pet from appearing.
• After PR pet: add spin, heart, yap, and clap #327412: two images are created hidden. A newly loaded image is revealed only inside _onImageLoad. That handler added a stale-load guard comparing normalized image.src with the original _pendingSource string.
• In packaged builds, spaces in the application path are percent-encoded by Chromium, the comparison fails, _onImageLoad returns early, and both images remain hidden.

[Copilot]

Pull request overview

Fixes pet sprite loading when Chromium URL-normalizes paths containing spaces.

Changes:

• Compares raw src attributes instead of normalized URL properties.
• Adds regression coverage for encoded application paths.

Show a summary per file

File	Description
chatPetWidget.ts	Corrects sprite source matching.
chatPetWidget.test.ts	Tests URL-normalization behavior.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Medium