codemesh doctor preflight with strict mode

[BramVR]

Parent

#70

What to build

Add codemesh doctor as an agent handoff preflight that uses the same Readiness Decision semantics as agent prepare without creating a run. Add strict mode so warning-only readiness can fail for automation without changing normal agent prepare behavior.

Acceptance criteria

• doctor reports handoff green or actionable blockers for a selected project.
• doctor creates no agent run directory and records no Agent Run.
• doctor --strict promotes warnings to failure.
• doctor human and JSON output use Command Result/Presentation.
• Command Catalog, CLI help, command reference, and e2e are updated.

Blocked by

• Shared Readiness Decision for existing commands #72
• Command Result and status --json tracer #74