Improve calculation speed by converting 'std::string' to 'StringView'

[numeredev]

DESCRIPTION

Is your change request related to a problem? Please describe. Calculation speed could be enhanced by converting some std::string instances to a StringView, but it was not carried out everywhere.

Describe the solution you'd like Convert std::string to StringView whereever possible.

Describe possible alternatives you've considered A clear and concise description of any alternative solutions or features you've considered, if any.

Additional context Add any other context or screenshots about the feature request here.

(Do not write below this line)

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DEVS' SECTION

ANALYSIS

Evaluate, where that's possible (might require multiple iterations) and carry the change out.

IMPLEMENTATION STEPS

(see also our Wiki for implementation guidelines)

• Implement the necessary changes in a new branch created here on GitHub
• Test your implementation

DOCUMENTATION STEPS

(see also our Wiki for further information)

• Update the changes log
• Add comments to your implementation
• Add Doxygen documentation comments
• Create or update the documentation articles (*.NHLP and *.NDB files, if needed)
• Update the language strings (*.NLNG files, if needed)

PULL REQUEST

• Create a pull request for your changes
• Fill out the template
• Assign @numere-org/maintainers as reviewers