fix(nvs): fix hard-coded ns/key in bool overloads

[finger563]

Description

• Fix hard-coded ns/key in bool overloads
• Add additional functions to take string_views
• Add error codes and update logging
• Update example to test more cases
• Update readme

Motivation and Context

The bool overloads for the nvs functions had a copy/paste hard-coded namespace and key value. This fixes that issue. It also adds additional overloads for accepting std::string_view and updates the error codes to be NVS specific.

How has this been tested?

Building and running nvs/example on a QtPy ESP32S3.

Screenshots (if appropriate, e.g. schematic, board, console logs, lab pictures):

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation Update
• [ ] Hardware (schematic, board, system design) change
• [x] Software change

Checklist:

• [ ] My change requires a change to the documentation.
• [ ] I have added / updated the documentation related to this change via either README or WIKI

Software

• [x] I have added tests to cover my changes.
• [ ] I have updated the .github/workflows/build.yml file to add my new test to the automated cloud build github action.
• [x] All new and existing tests passed.
• [x] My code follows the code style of this project.

[github-actions[bot]]

:white_check_mark:Static analysis result - no issues found! :white_check_mark: