Add profiles field to doctor findings JSON example

[codeforester]

Problem

docs/doctor-findings.md shows the top-level check JSON shape with schema_version, status, and checks, but the actual basectl doctor --format json wrapper also emits profiles.

A consumer using the documentation as the contract would not know to expect that field.

Evidence:

• docs/doctor-findings.md currently shows { "schema_version": 1, "status": "ok", "checks": [] }.
• cli/python/base_dev/engine.py emits "profiles": list(profiles) in print_check_results() for JSON output.

Desired outcome

The doctor findings documentation should match the live JSON shape.

Scope

• Update the JSON example to include "profiles": [].
• Adjust surrounding prose only if needed to clarify when profile names appear.
• Keep the documented diagnostic item schema unchanged.

Non-goals

• Changing JSON output behavior.
• Redesigning the doctor findings schema.

Acceptance criteria

• The top-level JSON example includes profiles.
• The example remains valid JSON.
• Any docs tests that validate examples continue to pass.

Demo impact

None.