Pin Homebrew cask to v0.1.0-beta.2 with verified SHA256

[naufaldi]

Summary

Update the canonical Homebrew cask in mac-fan-ctrl to match the published v0.1.0-beta.2 release and the live naufaldi/homebrew-tap distribution.

Background

• Personal tap repo: https://github.com/naufaldi/homebrew-tap
• Users install via:

  brew tap naufaldi/tap
  brew trust naufaldi/tap
  brew install --cask fanguard

• v0.1.0-beta.2 is published on GitHub Releases

Acceptance Criteria

• homebrew-cask/Casks/fanguard.rb uses version 0.1.0-beta.2
• sha256 :no_check replaced with real DMG hash
• Cask file in mac-fan-ctrl matches what is shipped in naufaldi/homebrew-tap
• Change merged via PR

Definition of Done

• PR merged to main
• Homebrew install tested successfully from tap

[naufaldi]

PR opened: #60