Add --format json flag to organvm registry list command

[4444J99]

Description

The organvm registry list command currently outputs a human-readable table. For scripting and automation, a --format json flag would emit the results as JSON.

Context

The CLI already has --json output in some subcommands (e.g., organvm omega status --json). This issue is about adding consistent JSON output to registry list.

Implementation hints

• Entry point: src/organvm_engine/cli/registry.py
• The registry data is already loaded as dicts — just needs a conditional json.dumps() path
• Follow the pattern used in cli/omega.py for the --json flag

Acceptance criteria

• organvm registry list --format json outputs valid JSON array
• Each entry includes: name, organ, status, tier, public
• Existing table output remains default
• Tests added in tests/test_cli_registry.py

Estimated effort

~30 minutes for someone familiar with Click/Typer CLI patterns.

[4444J99]

Backlog engagement 2026-07-19 — disposition: distilled.

Verified delivered on current main: organvm registry list documents and parses --format {table,json} in src/organvm_engine/cli/__init__.py, and src/organvm_engine/cli/registry.py::cmd_registry_list emits JSON when --format json or --json is set. Leaving the issue open per backlog doctrine, but the requested CLI behavior exists.