refactor: the person page reads before it writes

It opened as a wall of input boxes. Nearly every visit is someone
checking a fact, not changing one, and a page of open fields is both
harder to read and an invitation to change something by accident —
blur-to-save meant a stray click in the notes box was a write.

Details is one card now, displayed plainly, with an Edit button. Name,
company, notes and the opt-out switch become a draft you commit with
Save or throw away with Cancel; the draft re-seeds from props on every
entry, so reopening after a background refresh can't silently undo what
landed in between.

Addresses and custom fields stay immediate, and say so. They aren't
edits to a value, they're discrete acts with their own button — a row
that visibly disappeared but came back on Cancel would be worse than
one that just goes. Their remove buttons only exist in edit mode, so
the read view has nothing to misfire on.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CY9GSvGD8JYnMyU5Q6BW5r

Author: byw1