refactor: rename stock-lab → stock (graduation)

- git mv stock-lab/ → stock/
- docker-compose.yml: 서비스 키 + container_name + build.context +
  frontend.depends_on + agent-office STOCK_LAB_URL → STOCK_URL
- agent-office/app: config.py, service_proxy.py, agents/stock.py, tests/
  STOCK_LAB_URL → STOCK_URL
- nginx/default.conf: proxy_pass http://stock-lab → http://stock (3 lines)
- CLAUDE.md / README.md / STATUS.md / scripts/ 문구 갱신
- stock/ 내부 자기 참조 갱신

lab 네이밍 정책 (feedback_lab_naming.md) graduation.
API URL / Python import / DB 파일명 변경 없음.

stock/app/test_screener_schema.py

@@ -0,0 +1,37 @@
+import sqlite3
+from app.screener.schema import ensure_screener_schema
+
+
+def test_creates_all_tables(tmp_path):
+    db_path = tmp_path / "test.db"
+    conn = sqlite3.connect(db_path)
+    ensure_screener_schema(conn)
+
+    tables = {r[0] for r in conn.execute(
+        "SELECT name FROM sqlite_master WHERE type='table'"
+    ).fetchall()}
+
+    expected = {
+        "krx_master", "krx_daily_prices", "krx_flow",
+        "screener_settings", "screener_runs", "screener_results",
+    }
+    assert expected.issubset(tables)
+
+
+def test_settings_seeded_with_singleton_row(tmp_path):
+    db_path = tmp_path / "test.db"
+    conn = sqlite3.connect(db_path)
+    ensure_screener_schema(conn)
+
+    rows = conn.execute("SELECT id FROM screener_settings").fetchall()
+    assert rows == [(1,)]
+
+
+def test_idempotent(tmp_path):
+    db_path = tmp_path / "test.db"
+    conn = sqlite3.connect(db_path)
+    ensure_screener_schema(conn)
+    ensure_screener_schema(conn)        # 두 번 호출해도 에러 없어야 함
+
+    rows = conn.execute("SELECT count(*) FROM screener_settings").fetchall()
+    assert rows == [(1,)]