  We perform high-resolution three-dimensional general-relativistic
magnetohydrodynamic simulations with neutrino transport of binary neutron star
(BNS) mergers resulting in a long-lived remnant neutron star, with properties
typical of galactic BNS and consistent with those inferred for the first
observed BNS merger GW170817. We demonstrate self-consistently that within
$\lesssim\!30$ ms post-merger magnetized ($\sigma\sim 5-10$) twin polar jets
emerge with asymptotic Lorentz factor $\Gamma\sim 5-10$, which successfully
break out from the merger debris within $\lesssim\!20$ ms. A fast ($v\lesssim
0.6c$), magnetized ($\sigma\sim 0.1$) wind surrounds the jet core and generates
a UV/blue kilonova precursor on timescales of hours, similar to the precursor
signal due to free neutron decay in fast dynamical ejecta. Post-merger ejecta
are quickly dominated by MHD-driven outflows from an accretion disk. We
demonstrate that within only 50 ms post-merger, $\gtrsim 2\times
10^{-2}M_\odot$ of lanthanide-free, quasi-spherical ejecta with velocity
$\sim\!0.1c$ is launched, yielding a kilonova signal consistent with GW170817
on timescales of $\lesssim\!5$\,d.
