🎨 Palette: Add visual keyboard shortcut to Run button

[saint2706]

💡 What: Added a visual "Shift+Enter" hint to the Run button in Python code playgrounds and a tooltip to the Reset button.
🎯 Why: To improve discoverability of keyboard shortcuts and button functions for better UX and accessibility.
📸 Before/After: Screenshot verified.
♿ Accessibility: Maintains existing ARIA labels while adding visual cues for sighted users.

---

PR created automatically by Jules for task 11077410658317906139 started by @saint2706

[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.

[Copilot]

Pull request overview

Improves the Python playground UX by making key actions more discoverable: adds a visible keyboard shortcut hint to the Run button and a tooltip to the Reset button, alongside some small formatting-only refactors.

Changes:

• Add a visible Shift+Enter shortcut hint next to the Run button label in PythonRunner.
• Add a title tooltip to the Reset button in CodePlayground.
• Apply minor formatting refactors to link safety utilities and the Markdown link renderer.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/components/PythonRunner.tsx	Adds a visible <kbd> “Shift+Enter” hint to the Run button label.
src/components/CodePlayground.tsx	Adds a title attribute tooltip for the Reset button.
src/utils/linkSafety.ts	Formatting-only changes to the secure link attribute helper.
src/components/MarkdownRenderer.tsx	Formatting-only change to the rendered <a> tag.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.