🎨 Palette: Add ARIA button roles and Spacebar support to modal triggers

[0m364]

💡 What: Added role="button" and aria-haspopup="dialog" to all <a href="#"> tags acting as buttons for the "Sitrep" modal. Handled keydown events for the Space key to open the modal properly.

🎯 Why: Anchor tags (<a> with href="#") lack inherent button semantics. Screen readers might misinterpret their role, and they don't natively trigger with the Space key, disrupting the expected keyboard navigation flow.

📸 Before/After: Visual presentation is identical. Non-visual usage (screen readers, keyboard-only access) is highly improved.

♿ Accessibility: Ensures that keyboard-only users and screen readers understand that the Sitrep links act as buttons opening dialogs. It fully mimics native button behavior across interactions.

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PR created automatically by Jules for task 2348731864699853036 started by @0m364

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