fix(macos_container): mount supervise db's parent dir, not the file

Apple's `container run --mount type=bind` only accepts directory
sources — a file source fails with "path '<file>' is not a
directory". Move the sqlite db into its own ~/.bot-bottle/db/
subdirectory so it can be bind-mounted the same way the CA/routes
mounts already are, without exposing the rest of ~/.bot-bottle.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

tests/unit/test_macos_container_launch.py

@@ -139,7 +139,7 @@ class TestMacosContainerLaunchArgv(unittest.TestCase):
             argv,
         )
         self.assertIn(
-            "type=bind,source=/state/bot-bottle.db,target=/run/supervise/bot-bottle.db",
+            "type=bind,source=/state,target=/run/supervise",
             argv,
         )