feat: unify scheduled tasks from #337 and #338 with security-first integration

Unifies scheduled task capabilities and consolidates overlapping implementations from #337 and #338 into a single security-first integration path.\n\nCo-authored-by: Edvard <ecschoye@stud.ntnu.no>\nCo-authored-by: stawky <stakeswky@gmail.com>

src/main.rs

@@ -234,11 +234,28 @@ enum CronCommands {
         /// Command to run
         command: String,
     },
+    /// Add a one-shot delayed task (e.g. "30m", "2h", "1d")
+    Once {
+        /// Delay duration
+        delay: String,
+        /// Command to run
+        command: String,
+    },
     /// Remove a scheduled task
     Remove {
         /// Task ID
         id: String,
     },
+    /// Pause a scheduled task
+    Pause {
+        /// Task ID
+        id: String,
+    },
+    /// Resume a paused task
+    Resume {
+        /// Task ID
+        id: String,
+    },
 }
 
 #[derive(Subcommand, Debug)]