fix(desktop,mobile): user pickers search by substring, not prefix

Flip the user-search filters from search_mode="prefix" to "contains" so
every picker surface (member add, @mentions, DM recipients, topbar
people) matches any typed fragment of a name. Message typeahead stays on
prefix.

Co-authored-by: Cursor <cursoragent@cursor.com>

desktop/src-tauri/src/commands/profile.rs

@@ -172,7 +172,7 @@ fn build_user_search_filter(query: &str, limit: usize, page: u32) -> serde_json:
     serde_json::json!({
         "kinds": [0],
         "search": query,
-        "search_mode": "prefix",
+        "search_mode": "contains",
         "limit": limit,
         "page": page,
     })
@@ -236,12 +236,14 @@ pub async fn search_users(
     // than a substring hit in `about`. The caller can request later pages via the
     // cursor so the UI cap is only a page size, not a terminal directory ceiling.
     //
-    // `search_mode: "prefix"` matters: every caller of this command is a
+    // `search_mode: "contains"` matters: every caller of this command is a
     // typeahead surface (member picker, @mention popup, DM recipient search,
-    // topbar people results), so a partially typed name must match. Without it
-    // the relay runs whole-word `websearch_to_tsquery` matching and "tyl"
-    // returns zero results for "Tyler". Same bridge-only extension the topbar
-    // message search uses (see `build_search_messages_filter`).
+    // topbar people results), so any typed fragment of a name must match.
+    // Whole-word FTS returns zero results for "tyl" → "Tyler", and prefix
+    // mode returns zero results for "kurs" → "mattkursmark" because the name
+    // is a single lexeme. Contains mode is ILIKE substring matching on the
+    // relay (same bridge-only `search_mode` extension family the topbar
+    // message search uses via `build_search_messages_filter`).
     let events = query_relay(&state, &[build_user_search_filter(trimmed, max, page)]).await?;
 
     let mut response = nostr_convert::rank_user_search_results(&events, trimmed, max);
@@ -336,15 +338,17 @@ mod tests {
     use super::*;
 
     #[test]
-    fn user_search_filter_requests_prefix_mode_for_typeahead() {
+    fn user_search_filter_requests_contains_mode_for_typeahead() {
         // Every caller of `search_users` is a typeahead surface. Whole-word
         // FTS matching returns zero results for a partially typed name
-        // ("tyl" for "Tyler"), which reads as "user doesn't exist" in the
-        // member picker and @mention popup. Pin the mode so it can't drift.
-        let filter = build_user_search_filter("tyl", 25, 1);
+        // ("tyl" for "Tyler"), and prefix matching returns zero results for
+        // a mid-name fragment ("kurs" for "mattkursmark"), which reads as
+        // "user doesn't exist" in the member picker and @mention popup. Pin
+        // the mode so it can't drift.
+        let filter = build_user_search_filter("kurs", 25, 1);
 
-        assert_eq!(filter["search"], serde_json::json!("tyl"));
-        assert_eq!(filter["search_mode"], serde_json::json!("prefix"));
+        assert_eq!(filter["search"], serde_json::json!("kurs"));
+        assert_eq!(filter["search_mode"], serde_json::json!("contains"));
         assert_eq!(filter["limit"], serde_json::json!(25));
         assert_eq!(filter["page"], serde_json::json!(1));
     }

mobile/lib/shared/relay/nostr_filters.dart

@@ -134,16 +134,17 @@ abstract final class NostrFilters {
 
   /// Global user search over kind:0 profiles (NIP-50 via the HTTP bridge).
   ///
-  /// `search_mode: "prefix"` is a Buzz bridge-only extension: every caller is
-  /// a typeahead surface, so a partially typed name must match ("rac" →
-  /// "raccoon"). Mirrors desktop's `build_user_search_filter`
-  /// (desktop/src-tauri/src/commands/profile.rs). Bridge-only — send through
-  /// `queryRelay`, not a WebSocket REQ.
+  /// `search_mode: "contains"` is a Buzz bridge-only extension: every caller
+  /// is a typeahead surface, so any typed fragment of a name must match
+  /// ("kurs" → "mattkursmark" — prefix matching misses mid-name fragments
+  /// because names are single FTS lexemes). Mirrors desktop's
+  /// `build_user_search_filter` (desktop/src-tauri/src/commands/profile.rs).
+  /// Bridge-only — send through `queryRelay`, not a WebSocket REQ.
   static NostrFilter searchUsers(String query, {int limit = 50}) => NostrFilter(
     kinds: [0],
     search: query,
     limit: limit,
-    extensions: const {'search_mode': 'prefix'},
+    extensions: const {'search_mode': 'contains'},
   );
 
   /// Deletions (kind:5) targeting event IDs.