docs: expand package README with comprehensive documentation (#11)

* docs: Initial plan

* docs: add comprehensive package README for NetEvolve.CodeBuilder

Co-authored-by: samtrion <3283596+samtrion@users.noreply.github.com>

* fix: Moved README to root

* docs: complete API reference with all available methods and overloads

Co-authored-by: samtrion <3283596+samtrion@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: samtrion <3283596+samtrion@users.noreply.github.com>
Co-authored-by: Martin Stühmer <me@samtrion.net>

Author: Copilot