Preserve explicit carousel tab selections

[cursor]

Bug and Impact

Selecting certain Core Areas carousel tabs could immediately revert to a neighboring tab after the smooth centering scroll settled. Reproduced in Chrome at 480px by clicking AI Penetration Testing and seeing the panel revert to Thick Clients, and at 1024px by clicking Thick Clients and seeing it revert to Web3 / Blockchain Security.

Root Cause

The scroll-sync debounce treated scrollIntoView movement from explicit click/keyboard selection as passive user scrolling, recomputed the active tab from viewport center, and overwrote the user's selected panel.

Fix

Mark explicit selections' centering scroll as programmatic, suppress the corresponding scroll-sync update, and initialize the active tab without triggering a centering scroll.

Validation

• Headless Chrome carousel regression across 280, 320, 375, 480, 640, 768, and 1024px: all tab clicks preserve the selected panel.
• Headless Chrome passive scroll-sync checks at 375, 480, and 1024px still update the panel.
• Static smoke checks for 5 HTML files, 1 CSS file, 52 href/src refs, local anchors/assets, _blank rel safety, CSS url() assets, and #focusPanel visibility override.
• Inline JavaScript syntax check for index.html and resume.html passed.