Constant FIRSTPARTY_SOURCES 

pub const FIRSTPARTY_SOURCES: &'static [(&'static str, &'static str)];

Every first-party .bynk source, paired with its unit name — the single list every consumer iterates: hover (describe_firstparty_symbol), completion (EMBEDDED_UNITS), and the parse guard (every_first_party_source_parses). Before this list each consumer kept its own hand-maintained copy, and bynk.locale/bynk.locale.types were added to none of them — so the whole locale surface hovered as nothing and was absent from completion (#901).

A view over UNITS, in its order, which is observable: hover takes the first source declaring a name, and completion lists units in this order. The firstparty_sources_cover_every_src_const drift guard (bynkc/tests/firstparty_sources.rs) fails if a *_SRC const is left out of UNITS.