ail check returns ok for a program that references an unbound
identifier inside an instance method's lambda body. The error
surfaces later at ail build as a degraded mono-pass diagnostic
(monomorphise_workspace: unknown identifier) without source
location, symbol kind, or "did you mean" candidates.
Cause: check_def at crates/ailang-check/src/lib.rs:1593 early-
returns Ok(()) for Def::Instance without walking method bodies.
The arm's comment promises instance-body typechecking from iter
22b.2; that wiring was never implemented. Only the workspace-
load coherence checks (Orphan/Duplicate/MissingMethod) touch
instance defs, and they inspect schema only, not the method-
body identifier graph.
This commit lands RED only. GREEN follows via implement mini-
mode.
Fixture: examples/bug_unbound_in_instance_method.ail
RED test: crates/ail/tests/unbound_in_instance_method_pin.rs
- check_fires_unbound_var_for_str_concat_in_instance_method_body
- check_json_unbound_var_in_instance_method_body
