Add Homebrew tap support

[ajianaz]

Description

Create a Homebrew tap so users can install cora-cli via brew install.

Acceptance Criteria

• Create homebrew-tap repo at ajianaz/homebrew-tap
• Formula automatically updated on release
• Document installation in README: brew tap ajianaz/tap && brew install cora-cli
• Add CI step to update Homebrew formula on release

Implementation Notes

Use a GitHub Action (like homebrew-tap/release-action or custom script) to bump the formula version and SHA256 on tag push.

[ajianaz]

Implemented in PR #24, merged to develop.