#179 cli: add JSON output to doberman doctor without changing health exits

[Anonymous]

Originally created by: fu351

Context

doberman doctor already builds structured CheckResult values through run_checks(), then renders them for humans. An opt-in JSON mode would let setup scripts consume those same health results while preserving the command's established healthy/unhealthy behavior.

Suggested starting points

• src/doberman/cli/main.py — the doctor command
• src/doberman/cli/doctor.py — CheckResult, CheckStatus, run_checks(), and health helpers
• tests/unit/test_cli_doctor.py

Acceptance criteria

• [ ] Add a --json option to doberman doctor.
• [ ] Emit exactly one valid JSON document on stdout when the option is used.
• [ ] Include each check's name, normalized status, and safe detail plus a small summary (for example, counts by status and overall health).
• [ ] Build the JSON from the existing run_checks() results rather than duplicating health-check logic.
• [ ] Keep output deterministic and avoid human table/formatting text on JSON stdout.
• [ ] Preserve the current human-readable output when --json is absent.
• [ ] Preserve the existing exit code for every equivalent healthy, warning, and critical-failure result set.
• [ ] Add tests for JSON parsing, healthy and unhealthy results, warning behavior, deterministic shape, default-output compatibility, and secret-safe output.

Suggested validation

Use CliRunner and monkeypatched run_checks() results so the test does not depend on the contributor's real hooks, database, key permissions, or home directory. Compare exit codes between default and JSON modes for the same result sets.

Out of scope

• Adding new doctor checks.
• Changing the pass/warn/fail rules of existing checks.
• Changing enrollment, hook installation, or key permissions.
• Replacing the default human-readable output.

Security and compatibility

Only serialize the existing redaction-safe health result representation. Do not add secrets, key material, policy contents, database rows, or environment values. Failures while preparing output must not incorrectly report the system as healthy.

See CONTRIBUTING.md (github.com) before opening a pull request.

[Anonymous]

Ticket changed by: fu351

• status: open --> closed