update data purging, re-enable channel selection

src/database/queries.js

@@ -95,7 +95,7 @@ const positionQueries = {
   `),
 
   deleteOldPositions: db.prepare(`
-    DELETE FROM positions WHERE timestamp < datetime('now', '-' || ? || ' days')
+    DELETE FROM positions WHERE timestamp < datetime('now', '-' || ? || ' hours')
   `),
 
   getPositionTrails: db.prepare(`
@@ -170,7 +170,7 @@ const messageQueries = {
   `),
 
   deleteOldMessages: db.prepare(`
-    DELETE FROM messages WHERE created_at < datetime('now', '-' || ? || ' days')
+    DELETE FROM messages WHERE created_at < datetime('now', '-' || ? || ' hours')
   `)
 };
 
@@ -199,7 +199,7 @@ const telemetryQueries = {
   `),
 
   deleteOldTelemetry: db.prepare(`
-    DELETE FROM telemetry WHERE timestamp < datetime('now', '-' || ? || ' days')
+    DELETE FROM telemetry WHERE timestamp < datetime('now', '-' || ? || ' hours')
   `)
 };