Module: lib Responsibility: compact diagnostic identity and public numeric error-code mapping. Does not own: rich diagnostic prose, Candid wire types, or runtime error construction. Boundary: maps rich internal diagnostic categories to stable compact public codes.
This crate intentionally contains no rich diagnostic prose or Candid wire
types. Production canister builds collapse diagnostics to numeric wire
codes before they cross the public canister boundary. Debug output is
numeric for the same reason: host tooling can recover labels from the code
table without making every wasm canister retain those labels.