release: v1.0.117 沉淀多数据源契约（SQLite 默认 + 可选 MySQL 云库）

新增 DATA_SOURCES.md、data-sources 示例与双后端 connection 骨架；CLI 与宿主 UI 可读写同一库。要求匠厂 Host ≥ 6.9.28。

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_db_backend.py

@@ -0,0 +1,49 @@
+# -*- coding: utf-8 -*-
+"""数据库后端选择：默认 SQLite，DSN 解析。"""
+from __future__ import annotations
+
+import os
+import unittest
+
+from _support import IsolatedDataRoot
+
+
+class TestDbBackend(unittest.TestCase):
+    def test_resolve_backend_defaults_to_sqlite(self) -> None:
+        with IsolatedDataRoot():
+            from db.backend import resolve_backend
+
+            self.assertEqual(resolve_backend(), "sqlite")
+
+    def test_parse_mysql_dsn(self) -> None:
+        with IsolatedDataRoot():
+            from db.backend import parse_mysql_dsn
+
+            params = parse_mysql_dsn("mysql://root:secret@192.168.0.20:3306/demo_db")
+            self.assertEqual(params["host"], "192.168.0.20")
+            self.assertEqual(params["port"], 3306)
+            self.assertEqual(params["user"], "root")
+            self.assertEqual(params["password"], "secret")
+            self.assertEqual(params["database"], "demo_db")
+
+    def test_resolve_backend_uses_mysql_dsn_from_env(self) -> None:
+        with IsolatedDataRoot():
+            from db.backend import resolve_backend
+
+            os.environ["MYSQL_DSN"] = "mysql://u:p@127.0.0.1:3306/t"
+            try:
+                self.assertEqual(resolve_backend(), "mysql")
+            finally:
+                os.environ.pop("MYSQL_DSN", None)
+
+    def test_describe_active_store_sqlite(self) -> None:
+        with IsolatedDataRoot():
+            from db.connection import describe_active_store
+
+            info = describe_active_store()
+            self.assertEqual(info["backend"], "sqlite")
+            self.assertIn("db_path", info)
+
+
+if __name__ == "__main__":
+    unittest.main()