[prop4n]

Adds a Logs entry in the left sidebar to view the daemon's activity live.

Backend

• internal/logbuf: a bounded in-memory ring buffer (default 1000 lines) that is
  also an slog.Handler wrapping the existing one, so lines still go to stdout.
  Captures time, level, message + inline attrs. Fans new lines to subscribers.
• App tees the daemon logger through the buffer at startup.
• Server: GET /api/v1/logs (retained snapshot) and GET /api/v1/logs/stream
  (new lines over SSE, with keepalive + write deadlines like the status stream).

Frontend

• A Logs nav item and LogsView.vue: loads the ring snapshot, then streams
  live lines, auto-scrolling to the bottom with a Follow/Pause toggle. Level is
  colour-coded (error/warn/info).

Tests

• logbuf: cap + snapshot order, attr capture, live subscribe.
• Routes registered (verified: 401 unauth on /logs and /logs/stream).
• Go + vitest suites, golangci-lint (v2), gofmt clean.

Lost on restart by design; the persistent per-resource history covers durable audit.