Function dedup_rendered_by_text 

pub fn dedup_rendered_by_text(rendered: &mut Vec<RenderedCandidate>)

5.5.G.23.insert-prep: cross-source visual dedup for the insert-completion popup (Phase 4.2.g.7 polish). Keeps the FIRST occurrence of each raw.text; subsequent rows with the same text drop out. Called after the ranker has sorted descending by score, so the surviving row is the highest-ranked entry per text — the buffer-words copy of outer outranks the tree-sitter copy at the spec’s 100/80 priority split, so the popup row for outer carries the buffer-words tag.

Selection / navigation / accept all index into the deduped vec naturally; this is the only place we coalesce rows across sources, and it runs before the popup paints.