Registry-native inspect commands.
Purpose
-------
Expose read-only registry inspection commands at the top-level registry CLI.
Responsibilities
----------------
- Wire ``show``, ``status``, and ``whoami`` commands.
- Resolve registry paths through standard discovery.
- Format read-model dataclasses for humans or JSON.
Diagnostics
-----------
Domain: OC_CHAT.MAIN
Levels:
L2 - lifecycle events
L3 - semantic details
L4 - deep tracing
Contracts
---------
- Every command in this module is read-only.
- Missing explicit plan lookups exit non-zero with a clear message.
Dependencies
------------
- oc_diagnostics (structured debug logging via _dbg)
- oc_chat.registry.backends.sqlite (SQLite backend)
- oc_chat.registry.discovery (registry path discovery)
- oc_chat.registry.readers (typed read projections)
- oc_chat.registry (Registry facade the read projections query)