Move to hour-resolution adverts

app/migrations.py

@@ -177,6 +177,13 @@ async def run_migrations(conn: aiosqlite.Connection) -> int:
         await set_version(conn, 20)
         applied += 1
 
+    # Migration 21: Enforce minimum 1-hour advert interval
+    if version < 21:
+        logger.info("Applying migration 21: enforce minimum 1-hour advert interval")
+        await _migrate_021_enforce_min_advert_interval(conn)
+        await set_version(conn, 21)
+        applied += 1
+
     if applied > 0:
         logger.info(
             "Applied %d migration(s), schema now at version %d", applied, await get_version(conn)
@@ -1252,3 +1259,27 @@ async def _migrate_020_enable_wal_and_auto_vacuum(conn: aiosqlite.Connection) ->
     logger.info("Journal mode set to %s", mode)
 
     await conn.commit()
+
+
+async def _migrate_021_enforce_min_advert_interval(conn: aiosqlite.Connection) -> None:
+    """
+    Enforce minimum 1-hour advert interval.
+
+    Any advert_interval between 1 and 3599 is clamped up to 3600 (1 hour).
+    Zero (disabled) is left unchanged.
+    """
+    # Guard: app_settings table may not exist if running against a very old schema
+    # (it's created in migration 9). The UPDATE is harmless if the table exists
+    # but has no rows, but will error if the table itself is missing.
+    cursor = await conn.execute(
+        "SELECT name FROM sqlite_master WHERE type='table' AND name='app_settings'"
+    )
+    if await cursor.fetchone() is None:
+        logger.debug("app_settings table does not exist yet, skipping advert_interval clamp")
+        return
+
+    await conn.execute(
+        "UPDATE app_settings SET advert_interval = 3600 WHERE advert_interval > 0 AND advert_interval < 3600"
+    )
+    await conn.commit()
+    logger.debug("Clamped advert_interval to minimum 3600 seconds")