fix(skills): raise registry card Install button above navigation overlay

[samuv]

On the Skills > Registry tab, clicking Install on a card would navigate to the skill detail page instead of opening the install dialog. The Local Builds and Installed tabs were unaffected.

Root cause

card-skill-base.tsx renders a full-card click overlay — an absolutely-positioned <span> pinned to inset-0 inside the title button — to make the whole card a navigation target. Because the overlay is absolutely positioned against the relative Card, it stacks above any statically-positioned descendant, including footer buttons. Siblings in the footer have to opt into their own stacking context (position: relative + a z-index) to receive their own clicks, otherwise the overlay captures the pointer and the card-level onClick runs instead.

Every other action button in the Skills cards already does this:

• card-build.tsx — Install and Remove use relative z-10.
• card-skill.tsx — Uninstall uses relative z-10.
• card-registry-skill.tsx — the sibling GitHub link uses relative z-10.

The Install button in card-registry-skill.tsx was the only one missing the escape hatch, so the overlay kept eating its clicks. The existing e.stopPropagation() on the handler was correct but never fired — the event never reached the button in the first place.

Changes

• card-registry-skill.tsx: add relative z-10 to the Install button's class list, matching the pattern used on the other Skills cards.

No logic, analytics, or markup changes beyond the class tweak.

Verification

• On Skills > Registry (both grid and table views), clicking Install opens the install dialog. Clicking the title or any empty area of the card still navigates to the skill detail page.
• Local Builds and Installed tabs behave as before.
• Existing tests in card-registry-skill.test.tsx — opens the install dialog when Install button is clicked and does not navigate when Install button is clicked — continue to pass; they exercise the onClick path via userEvent and are unaffected by the z-index fix.

[Copilot]

Pull request overview

Fixes an interaction bug in the Skills “Registry” tab where the card-level navigation overlay was intercepting clicks intended for the Install button, preventing the install dialog from opening.

Changes:

• Raise the Registry card Install button above the full-card navigation overlay by adding relative z-10 to its class list.