v0.1.0

Initial release. Six-band wurtzite k.p envelope-function solver with a self-consistent Poisson loop: exactly Hermitian discretization for position-dependent parameters, T=0 subband filling with numeric edge masses, and Gauss-law electrostatics for polarization-bound gases. Hard-wall boundaries only; a finite barrier is the v0.2 gate, and results are not yet validated against published subband structures, so do not use v0.1 numbers in publications. Ships no material constants by design; supply WurtziteParameters with cited provenance. Test suite (4 tests) runs on CI.