chore: automated gen of readme

ci: updated gha

refactor: enhanced code, removed redundancies

fix: added seed before call to minpack.lm

test: enhanced unit tests

test: added unit tests for new computation options

feat: working on implementing better guess for nls gauss-newton method

feat: added implementation of minpack.lm nls solving with good guess …

feat: preparing implementation of alternative algorithm using minpack.lm

fix: fixed implementation of nls_solver

refactor: common nls2-code to nls_solver fun

refactor: stopifnot with understandable msgs