🎨 Palette: Add Spacebar and ARIA support to OSINT Modal Buttons

[0m364]

💡 What: Added role="button" and aria-haspopup="dialog" to all instances of the "OSINT" (#sitrep-btn) links across concepts.html, products.html, and contact.html. Also updated modal.js to listen for the Spacebar keydown event and trigger the modal properly.

🎯 Why: The OSINT links look like buttons and function as triggers for a modal dialog, but they were using <a> tags. Screen readers announce them as navigation links rather than dialog-triggering buttons, and keyboard users expect buttons to activate with both Enter and Space.

📸 Before/After: No visual changes. Keyboard interaction is improved for spacebar pressing.

♿ Accessibility: Fixes incorrect semantics and improves keyboard support for the sitrep trigger.

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PR created automatically by Jules for task 3103760334757681454 started by @0m364

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