feat(cli): add cbh CLI resolving issues #226 #227 #228 #229

[villadel]

#226 – remove conflicts_with_all from --format; include webhook_checks
and horizon_checks arrays in JSON output; exit 1 on any failure.

#227 – replace check-then-write with OpenOptions::create_new for atomic
init; write config with 0600 permissions; --force uses truncate.

#228 – detect non-TTY stdin via IsTerminal and fail fast listing missing
flags; add --non-interactive flag for the same behaviour.

#229 – add --label, repeatable --rule presets (failed, admin,
large-transfer=N), and --horizon-url; validate --network before
any interactive prompting; custom network requires --horizon-url.

Also:

• scaffold cli/ Rust crate (clap 4, serde_json, reqwest blocking, toml)
• 15 unit tests covering all four issues
• .github/workflows/cli-tests.yml CI (fmt, clippy, build, test)
• .gitignore updated with Rust/Node artifacts, test snapshots, secrets

Pull Request

Summary

• Describe the purpose of this PR in one or two sentences.

Checklist

• PR description includes: Closes #[issue_id]
• Tests added or updated
• ABI snapshot updated if contract sources changed (abis/ and COMEBACKHERE-contracts/)
• Screenshots attached if UI changed
• Documentation updated if needed

Notes

• For contract changes, verify ABI snapshot hygiene with make check-abi-snapshots.
• For UI changes, include screenshots or screen recordings to help reviewers.

closes #226
closes #227
closes #228
closes #229