🧹 remove console.warn from production parser code

[ekayaprod]

🎯 What: Removed console.warn from js/parser.js where schema validation fails for an item.

💡 Why: console.warn should be restricted to transient network failures or critical issues in production code. Schema validation failures for individual items during streaming are expected edge cases and should be handled silently to avoid log pollution.

✅ Verification: Ran verify_tests.sh and confirmed all tests pass. Manually verified the removal of the line in js/parser.js.

✨ Result: Cleaner production logs and improved code health.

---

PR created automatically by Jules for task 1890422183967338669 started by @ekayaprod

[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.