Slow sim to 1× on landing and resume last selected speed (ISS-057, v0.30.0)

lib/db/client.ts

@@ -54,7 +54,8 @@ CREATE TABLE IF NOT EXISTS sim_state (
   clock_ms INTEGER NOT NULL,
   time_scale REAL NOT NULL,
   paused INTEGER NOT NULL,
-  last_real_tick_ms INTEGER NOT NULL DEFAULT 0
+  last_real_tick_ms INTEGER NOT NULL DEFAULT 0,
+  last_selected_time_scale REAL NOT NULL DEFAULT 1
 );
 `;
 
@@ -82,6 +83,12 @@ function migrateColumns(raw: RawSqlJsDatabase): void {
   if (!cols('packages').has('weight_kg')) {
     raw.exec('ALTER TABLE packages ADD COLUMN weight_kg REAL NOT NULL DEFAULT 2000');
   }
+  // v0.30.0 (ISS-057): last-selected speed — pre-existing rows backfill to the row's OWN
+  // current time_scale so a legacy DB resumes at the speed it was running, not the default.
+  if (!cols('sim_state').has('last_selected_time_scale')) {
+    raw.exec('ALTER TABLE sim_state ADD COLUMN last_selected_time_scale REAL NOT NULL DEFAULT 1');
+    raw.exec('UPDATE sim_state SET last_selected_time_scale = time_scale');
+  }
 }
 
 // v0.12.0 one-time migration: contracts world → packages world. Detected by the