Function handler_lens_sites 

pub fn handler_lens_sites(text: &str) -> Vec<Span>

Every on <kind> handler declaration in text, for the per-handler “Show Sequence” CodeLens. Not index_queries::code_lenses — that walks SymbolKind::Handler sites, which only agent handlers get (bynk-check/src/index.rs: “Service handlers have no per-handler name… so only agent dispatch is covered”); reusing it as-is would silently drop the lens for every service (non-agent) handler, which is most of them. A direct AST walk covers both uniformly.