Redesign settler cards from the Settler Showcase, and group parallel settlers into a crew

[ParallelEntrepreneur]

Implements the Settler Showcase design (claude.ai/design): the ant, the card and
parallel settlers.

The ant (AntAvatar.tsx, index.css) is now a pixel-art worker in side profile,
26 by 20 pixels with crisp edges and a joint for every moving part. The ground,
thought pixels, scribble and lens move a pixel at a time.

• working: a tripod gait, carrying what the tool is (a lens to search or read, a
  leaf to edit, a block to build or install, a flag to test).
• thinking: looks up while a thought fills in, dot by dot.
• writing: nods over a line it writes and rewrites.
• done: hops once and rests with a check.
• paused: sits with its antennae drooped.
• A failed tool result makes it stumble over a pebble, then carry on.
• Each role wears its own mark: a Scout's pack, a Builder's hard hat, an
  Inspector's monocle, and so on.
• Reduced motion freezes every state in a readable pose.

The card (SettlerCard.tsx) keeps the settler's name, task and one status line.
It adds a step count and a trail along its foot that moves while the settler
works, and the frame turns green when the settler is done. Collapsed, a done
card shows the first sentence of its report. Opened, it shows the report as
markdown, then the steps: in plain words with the command or path each acted
on, or the raw transcript in the technical view.

Grouping: settlers the orchestrator sends out together are one crew. Their
events interleave while they work, and each settler now keeps one card for the
whole burst instead of splitting into "continued" cards every time another
settler speaks. A crew's cards hang off one rail under a strip of its ants on a
shared trail ("3 settlers · 2 at work · 1 done"), and their loops are staggered
so they never move in lockstep.

Departures from the design, where it showed data colonies don't send:

• A done card doesn't show a duration, because the stream doesn't record when
  a settler finished.
• A failed step says "didn't work", not "didn't work · retried", because
  nothing says it was retried.

The mock's colony now sends a crew of three (Scout, Tester, Inspector) with a
failing test run, so ?mock=1 shows every part of this.