fix(tools): resolve config path inside container

tests/test_fans_csv.py

@@ -12,6 +12,7 @@ sys.stdout.reconfigure(encoding="utf-8")
 from reaction_board.database import Database  # noqa: E402
 from reaction_board.repository import Repository  # noqa: E402
 from tools.import_fans_csv import (  # noqa: E402
+    _database_path,
     import_fans_series,
     parse_fans_csv,
 )
@@ -104,6 +105,15 @@ def test_import_default_force_and_replace():
             db.close()
 
 
+def test_database_path_resolution():
+    assert _database_path("missing.json", "x.db") == Path("x.db")
+    with tempfile.TemporaryDirectory() as tmp:
+        from tests.web_fixtures import write_config
+
+        config = write_config(tmp)
+        assert _database_path(str(config), None) == Path(tmp) / "app.db"
+
+
 def test_replace_guard_for_newer_rows():
     series = parse_fans_csv(CSV_TEXT)
     with tempfile.TemporaryDirectory() as tmp:
@@ -147,6 +157,7 @@ def main_test():
     test_parse_csv()
     test_parse_rejects_bad_values()
     test_import_default_force_and_replace()
+    test_database_path_resolution()
     test_replace_guard_for_newer_rows()
     test_replace_dry_run_counts_only()
     print("OK: 粉丝 CSV 解析/导入/替换/幂等测试全部通过")