Redesign skill detail to card-hero layout

Make the minted 1:1 card image the hero of the skill detail view
(design "Skill Detail - Card Hero", direction 1), framed by accent-green
bracket corners. Drop the redundant icon + title + description head
since the wordmark is baked into the art; keep a visually-hidden h1 for
accessibility. Move the actions (Buy / Owned + Unequip) directly under
the card and add a meta line for holders, price, and the Magic Eden link.

Re-lay the body as terminal > sections: full untruncated ABOUT with live
hashtag chips, required skills, used-by repos, SKILL TEXT, and COMMENTS.
Items without a card image degrade to the sigil-icon + Chakra Petch title
head. Comment gating is unchanged: owners get the composer, non-owners
get the collect-to-comment gate, wallet-less users get connect-to-comment.

Author: zo-sol