Lexical coverage gate for matching; fix demo false positive

src/node.rs

@@ -310,7 +310,9 @@ impl Node {
         let max = max_results.unwrap_or(self.config.query.max_results).max(1);
         let query = QueryBody::new(text, max);
         let qid = query.qid.clone();
-        let (local_hits, local_total) = self.index.search(text, max, false)?;
+        let (local_hits, local_total) =
+            self.index
+                .search_with_coverage(text, max, false, self.config.matching.min_coverage)?;
         let local_items = response_items(&local_hits);
         let mut responses = Vec::new();
         if network {
@@ -560,7 +562,12 @@ impl Node {
 
     async fn respond(&self, query: &QueryBody, querier: &str, relay: &str) -> Result<()> {
         let max = query.budget.max_results.clamp(1, 1000);
-        let (hits, total) = self.index.search(&query.text, max, true)?;
+        let (hits, total) = self.index.search_with_coverage(
+            &query.text,
+            max,
+            true,
+            self.config.matching.min_coverage,
+        )?;
         if hits.is_empty() {
             return Ok(());
         }