Feature&Refactor: plan to change datatypes of all flags `out_*` from `bool/int` to `std::vector<int>` inside ABACUS to support seperate output precision control

[kirk0830]

Describe the Code Quality Issue

The output of Hamiltonian and overlap matrix with precision 5 is actually unacceptable for scientific calculation purpose, the same problem also exists in out_chg, the loss of precision would cause extra number of scf loops in restarted run. Postprocessing like Bader charge analysis also needs relatively high precision of cube file.
Based on PR #3454 , after changing from bool/int to std::vector<int> which contains two elements, the first element in vector would be identical with the original, for selecting option, the second would be precision.
Default value will give the second.

Keywords to support:

Keyword	Description
out_mul	Mulliken charges
out_chg	charge density cube file
out_pot	potential cube file
out_dm	density matrix (gamma-only)
out_dm1	density matrix (multiple k points)
out_wfc_pw	wavefunctions in plane wave basis
out_wfc_r	wavefunctions in real space
out_wfc_lcao	wavefunctions in LCAO basis
out_dos	density of states
out_band	band structure
out_proj_band	projected band structure
out_mat_hs	Hamiltonian H(k) and overlap S(k) matrices
out_mat_r	H(R) and S(R)
out_mat_t	T(R)
out_mat_dh	dH(R)/dR
out_mat_xc	exchange-correlation matrix

Checklist:

• out_mul
• out_chg
• out_pot
• out_dm
• out_dm1
• out_wfc_pw
• out_wfc_r
• out_wfc_lcao
• out_dos
• out_band
• out_proj_band
• out_mat_hs
• out_mat_r
• out_mat_t
• out_mat_dh
• out_mat_xc

[WHUweiqingzhou]

Very good refactor!