6.17.4 "Building in public" status badge + stop/manage path

Estimate: 35m · Type: code · Depends on: 6.17.1, 6.17.2

The "Building in public" status indicator — a badge/pill shown on the project (header and/or settings, per 6.17.1) when access = public, with a manage / "Stop building in public" path (admin-gated; confirm via the 6.17.2 reverse dialog; flips back to the prior/open level via setAccessLevel). Makes the public state legible as a status, not a hidden setting.

Acceptance criteria

• Public projects show the "Building in public" badge; admins get a stop/manage action; non-admins see the badge read-only.
• Stop → confirm → project leaves public; status badge clears; --el-*/Pill tones; matches 6.17.1.

Context refs

• project header/shell + settings; projectsService.setAccessLevel; components/ui/Pill; design 6.17.1