Bug: It seems that the electric field force in RT-TDDFT is not applied at all, and the wrong function was called as well

[AsTonyshment]

Describe the bug

When I was debugging issue #5333, I found this in module_hamilt_lcao/hamilt_lcaodft/FORCE_STRESS.cpp:

abacus-develop/source/module_hamilt_lcao/hamilt_lcaodft/FORCE_STRESS.cpp

Lines 272 to 278 in 105fd19

	//! atomic forces from E-field of rt-TDDFT
	ModuleBase::matrix fefield_tddft;
	if (PARAM.inp.esolver_type == "TDDFT" && isforce)
	{
	fefield_tddft.create(nat, 3);
	elecstate::Efield::compute_force(ucell, fefield_tddft);
	}

This piece of code has three issues:

• String case mismatch: The string for PARAM.inp.esolver_type should be "tddft" in lowercase, not "TDDFT" in uppercase. Due to this, this branch is skipped, which means the electric field force in RT-TDDFT is not applied at all.
• Incorrect function call: Why is compute_force from the elecstate::Efield class being called here? It’s unrelated to the RT-TDDFT algorithm. Instead, we should be calling H_TDDFT_pw::compute_force:

  abacus-develop/source/module_elecstate/potentials/H_TDDFT_pw.cpp

  Lines 482 to 496 in 105fd19

  	void H_TDDFT_pw ::compute_force(const UnitCell& cell, ModuleBase::matrix& fe)
  	{
  	int iat = 0;
  	for (int it = 0; it < cell.ntype; ++it)
  	{
  	for (int ia = 0; ia < cell.atoms[it].na; ++ia)
  	{
  	for (int jj = 0; jj < 3; ++jj)
  	{
  	fe(iat, jj) = ModuleBase::e2 * amp * cell.atoms[it].ncpp.zv * bvec[jj] / bmod;
  	}
  	++iat;
  	}
  	}
  	}

• Formula issue: Even in the function H_TDDFT_pw::compute_force, the force formula seems incorrect. The amp variable is just a constant amplitude that doesn’t change with time. This should likely be replaced with vext_time or something else. It is worth noting that the H_TDDFT_pw::compute_force function is never called anywhere in the entire program.