wire reminder ops into the in-agent socket dispatch (#2635 inc 1)

hive-agent/src/vacuum.rs

@@ -28,6 +28,10 @@ const BASH_KEEP_SECS: i64 = 48 * 3600;
 /// kinds are never deleted by this sweep — they carry the semantic per-turn
 /// history the operator scrolls back through.
 const STREAM_KEEP_SECS: i64 = 14 * 24 * 3600;
+/// Keep delivered (soft-deleted, `sent_at` set) reminder rows this long
+/// before reaping them — same window as `STREAM_KEEP_SECS`, kept around
+/// only to serve the trailing-window `ReminderRollup` stats.
+const REMINDER_KEEP_SECS: i64 = 14 * 24 * 3600;
 /// Terminal bash-task statuses whose files are eligible for deletion.
 const TERMINAL_STATUSES: &[&str] = &["done", "timed_out", "interrupted"];
 
@@ -60,6 +64,24 @@ fn sweep_once() {
             Err(e) => tracing::warn!(error = ?e, "events vacuum failed"),
         }
     }
+
+    let reminders_db = crate::paths::reminders_db();
+    if reminders_db.exists() {
+        match vacuum_reminders(&reminders_db) {
+            Ok(0) => {}
+            Ok(n) => tracing::info!(removed = n, "reminders vacuum"),
+            Err(e) => tracing::warn!(error = ?e, "reminders vacuum failed"),
+        }
+    }
+}
+
+/// Reap delivered reminder rows older than [`REMINDER_KEEP_SECS`] via the
+/// typed store API (own short-lived connection — mirrors `vacuum_events`'s
+/// own connection to `events.sqlite` rather than sharing the harness's live
+/// `Reminders` handle).
+fn vacuum_reminders(path: &Path) -> anyhow::Result<usize> {
+    let store = crate::reminders::Reminders::open(path)?;
+    store.prune_delivered_older_than(now_unix() - REMINDER_KEEP_SECS)
 }
 
 /// Delete eligible bash-task trios in `dir`. Returns the count of `.json`