myclaude -r: unify resume picker with xiaohe client sessions

Bare -r/--resume now opens a numbered picker merging jsonl (source of
truth) with the xiaohe hosted-session index, deduped by cli_session_id
and sorted by real content activity (not jsonl mtime, which the xiaohe
projection re-touches). -l gains a Src column (xiaohe/cli); -r <id> and
-c stay passthrough. Adds read-only xiaohe_sessions data layer + tests.

tests/test_entrypoints.py

@@ -37,6 +37,22 @@ class TestMyclaudeEntrypoint:
         assert "myclaude" in result.output
 
     def test_passthrough(self, tmp_path: Path) -> None:
+        """``--resume <id>`` still passes through to the native CLI."""
+        runner = CliRunner()
+        with (
+            patch("myagents.launcher.shutil.which", return_value="/usr/bin/claude"),
+            patch("myagents.launcher.subprocess.run") as mock_run,
+        ):
+            mock_run.return_value = MagicMock(returncode=0)
+            result = runner.invoke(
+                claude_cli, ["--cwd", str(tmp_path), "--resume", "abc123"]
+            )
+            assert result.exit_code == 0
+            args = mock_run.call_args[0][0]
+            assert args[-2:] == ["--resume", "abc123"]
+
+    def test_bare_resume_opens_picker(self, tmp_path: Path) -> None:
+        """Bare ``--resume`` opens the unified picker instead of the CLI."""
         runner = CliRunner()
         with (
             patch("myagents.launcher.shutil.which", return_value="/usr/bin/claude"),
@@ -45,7 +61,7 @@ class TestMyclaudeEntrypoint:
             mock_run.return_value = MagicMock(returncode=0)
             result = runner.invoke(claude_cli, ["--cwd", str(tmp_path), "--resume"])
             assert result.exit_code == 0
-            assert "--resume" in mock_run.call_args[0][0]
+            mock_run.assert_not_called()
 
 
 class TestMykimiEntrypoint: