0.2.110

docs: record what the first real code review taught us

A session note and four additions to the code-review concept in claude.md,
because four of the things below were declared in the design and never actually
ran — and nothing in a typecheck or a test was going to say so.

The session note covers the shadowing bug in full: fleetd's terminal event is
its own summary of the RUN, not the agent's words, and preferring it meant the
agent's real final message was never read. True of the fleet and not of the
Agent SDK, which is why the reading looked right.

claude.md gains what a future session would otherwise re-derive or repeat:

- Depth means model tier, the judging passes escalate on every preset, and
  escalation must happen after the model ladder — with the cross-vendor trap
  spelled out, because fleetProviderForModel's anthropic default is correct for
  choosing a credential and dangerous for choosing a model.
- The judge's verdict carries a severity and a reason, and both used to be
  discarded.
- Auto-fix exists, is off, and what bounds it — including that each bound came
  from a finding that was actually wrong.
- Lens names are user-facing now, and why that reverses the original rule
  without contradicting the reasoning behind it.