feat: complete evidence restructuring worktree

harness/tests/test_evidence_cli.py

@@ -21,10 +21,40 @@ def test_evidence_authoring_commands_are_distinct_from_runtime_preprocessing():
 
     assert result.exit_code == 0
     assert "prepare" in result.output
+    assert "migrate" in result.output
     assert "resolve" in result.output
     assert "validate" in result.output
 
 
+def test_evidence_migrate_json_is_pristine(monkeypatch, tmp_path):
+    from tht.cli import evidence_cmd
+    from tht.evidence import EvidenceMigrationReport
+
+    monkeypatch.setattr(evidence_cmd, "_canonical_worktree", lambda root: root)
+    monkeypatch.setattr(
+        evidence_cmd,
+        "migrate_workspace_evidence",
+        lambda *args, **kwargs: EvidenceMigrationReport(
+            migrated=("evidence:fascia-pediatrica",),
+            unchanged=("evidence:fascia-adulta",),
+            findings=(),
+        ),
+    )
+
+    result = CliRunner().invoke(app, ["evidence", "migrate", str(tmp_path), "--json"])
+
+    assert result.exit_code == 0
+    assert result.stderr == ""
+    assert json.loads(result.stdout) == {
+        "findings": [],
+        "migrated": ["evidence:fascia-pediatrica"],
+        "operation": "evidence_migrate",
+        "schemaVersion": 1,
+        "status": "migrated",
+        "unchanged": ["evidence:fascia-adulta"],
+    }
+
+
 def test_evidence_prepare_failure_identifies_the_source_file(monkeypatch, tmp_path):
     from tht.cli import evidence_cmd
     from tht.evidence import EvidencePreparationError