refactor(cli): add --version and -V flags to CLI

[XiaoPengYouCode]

Summary

This PR adds CLI version flags (--version, -V) and makes version lookup consistent across source and dist execution paths.

What changed

• Added --version / -V parsing and help/README docs.
• Introduced shared helper src/utils/version.ts for:
  • readVersion()
  • findProjectRoot()
• Reused the helper in cli, daemon, and daemon-client to remove duplicated logic.
• Added smoke coverage for both --version and -V.

Usage

$ agent-device --version
0.3.0

$ agent-device -V
0.3.0

Closes #43

[thymikee]

Thanks!