VQkit v1.1 QE band-structure update

1. Detect QE Fermi energy from pw.x output.
2. Search clearly named nearby SCF/NSCF folders when the band folder has no Fermi value.
3. Shift all plotted/exported QE band energies as E - E_F.
4. Automatically use compatible local KPATH_INTERPOLATED.dat or QE crystal_b path metadata.
5. No interactive K-path metadata selection prompt.
6. Matplotlib x-axis uses high-symmetry labels when safely mapped.
7. Export VQkit_HIGH_SYMMETRY_ENERGIES.dat with shifted band energies at symmetry points.
8. Preserve numerical k-path plotting when labels are unavailable.
