bloc-v8.0.2

• fix: make onChange and addError protected (#3071)
• refactor: use late keyword for internal state controller (#3100)
• refactor: add isClosed to Closable (#3066)
• refactor: add core interfaces (#3012)
• refactor: internal reorganization (#3011)
• docs: update example to follow naming conventions (#3029)

Thanks to @purplenoodlesoop! 🎉 💙