ADR-0115: One environment-variable name template, and key_id stays a segment in it

Status: accepted

Context

The design lists six segments and excludes key_id on the grounds that it is identity rather than a value. True of what it means, false of what it already does: dotenvKey has put it in the name since Phase 3, env-link.ts scores PROVIDER_KEYID as a tier-1 match, and find_entry parses a bare ${NAME} by splitting into exactly that pair. Dropping it silently renames every variable a keyed entry generates — the failure the design's own "must not break" section is about — for nothing

Decision

One environment-variable name template, and key_id stays a segment in it

Evidence

src/ts/state.ts, unv-cli/src/envfile.rs