docs: Update documentation and known issues

[rpsec]

Updated README.md, docs/setup.md, docs/development.md, AGENTS.md, and GEMINI.md to accurately represent the plugin's features and current limitations. Removed the outdated note about Windows platform archive support, corrected the github repository URL, and added test verification steps to the release process.

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PR created automatically by Jules for task 188177063360414320 started by @rpsec

[google-labs-jules]

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