UI updates staged behind debug mode flags. Initial new views added
in app.tsx, rendered based on the current debug setting.
Updates tailscale/corp#14335
Signed-off-by: Sonia Appasamy <sonia@tailscale.com>
Also allows us to use absolute import paths (see change in index.tsx).
Updates tailscale/corp#13775
Signed-off-by: Sonia Appasamy <sonia@tailscale.com>