Add due_time field to Todo tasks

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker/schema_family.sql

@@ -334,6 +334,7 @@ CREATE TABLE IF NOT EXISTS pf_todos (
   title      VARCHAR(500) NOT NULL,
   notes      TEXT DEFAULT NULL,
   due_date   DATE DEFAULT NULL,
+  due_time   TIME DEFAULT NULL,
   priority   ENUM('none','low','medium','high') DEFAULT 'none',
   done       TINYINT(1) DEFAULT 0,
   done_at    DATETIME DEFAULT NULL,