inspection_envelope and render_inspection_json are in __all__ with no user documentation

[codeforester]

Problem

base_cli.__all__ exports two symbols with no user-facing documentation anywhere in the repository:

• inspection_envelope — creates a structured JSON envelope for read-only inspection commands
• render_inspection_json — renders that envelope to stdout

These are backed by lib/python/base_cli/inspection.py. The inspection schema (schema_version / command / status / data / error) is distinct from the success/error envelopes documented in docs/json-contracts.md.

docs/api-stability.md states:

The supported Python facade is import base_cli. The names in base_cli.__all__ are the public facade; documented names in the explicitly exported modules are public as well.

The key word is documented. These two symbols are in __all__ and therefore carry a stability commitment, but they have no documentation — not in json-contracts.md, not in output-contracts.md, not in the README, not in any doc file. This directly contradicts the stability contract.

Concrete impact

A consumer who discovers inspection_envelope from IDE autocomplete or dir(base_cli) has no way to know:

• What an "inspection command" is vs. a regular command
• What the envelope schema looks like
• When to use it vs. success_envelope / error_envelope
• What version guarantees apply to the schema

Fix

Add a dedicated section to docs/json-contracts.md documenting:

1. What an inspection command is (read-only, state-querying, idempotent)
2. The envelope schema with a concrete example
3. When to use inspection_envelope vs. success_envelope
4. The schema_version value and stability guarantee

If these symbols are not yet ready for a stability commitment, move them to base_cli.experimental and remove from __all__ until they are documented.