refactor: fix completion updates

src/tui/mode/overlay/completion_dropdown.zig

@@ -137,6 +137,7 @@ fn update_query(self: *Type, cursor: ed.Cursor) error{OutOfMemory}!void {
         else => |e_| return e_,
     };
     defer self.allocator.free(query);
+    self.update_query(query) catch return;
     tp.self_pid().send(.{ "cmd", "completion" }) catch |e| self.logger.err(module_name, e);
     return;
 }

src/tui/mode/overlay/dropdown.zig

@@ -267,6 +267,7 @@ pub fn Create(options: type) type {
         }
 
         pub fn update_query(self: *Self, query: []const u8) !void {
+            self.query.clearRetainingCapacity();
             try self.query.appendSlice(self.allocator, query);
             return self.start_query(0);
         }