feat: full IDX universe (780 ticker) — universe table + close sweep harian, dashboard foreign-flow picker dari semua ticker, rotateDepth incremental fill 10/cylcle, strip .JK, backfill cmd/universe-sweep

backend/internal/store/migrations/0009_universe.sql

@@ -0,0 +1,6 @@
+-- 0009_universe.sql: persisted full IDX ticker universe from the close sweep.
+CREATE TABLE IF NOT EXISTS universe(
+  ticker TEXT PRIMARY KEY,
+  close INTEGER NOT NULL DEFAULT 0,
+  date TEXT NOT NULL DEFAULT ''
+);