fix(flr): treat MountCompletedSuccessfully as ready and use v1/downloads tokens

Lab 10.9 GET /v1/flrs/{id} returns a list with FlrSessionStatus, not a dict Status.
Download returns a path like v1/downloads/{id}, not a bare token.

tests/test_recover.py

@@ -1,12 +1,30 @@
-from zerto_rewind_mcp.recover import download_token_from, session_id_from
+from zerto_rewind_mcp.recover import (
+    download_token_from,
+    flr_row,
+    flr_status,
+    session_id_from,
+)
 
 
 def test_session_id_shapes():
     assert session_id_from("abc") == "abc"
     assert session_id_from({"sessionId": "s1"}) == "s1"
     assert session_id_from({"Identifier": "s2"}) == "s2"
+    assert session_id_from({"FlrSessionIdentifier": "s3"}) == "s3"
 
 
 def test_download_token_shapes():
     assert download_token_from("tok") == "tok"
     assert download_token_from({"downloadToken": "t2"}) == "t2"
+    assert download_token_from("v1/downloads/abc").startswith("v1/")
+
+
+def test_flr_list_status():
+    payload = [
+        {
+            "FlrSessionStatus": "MountCompletedSuccessfully",
+            "FlrSessionIdentifier": "sess-1",
+        }
+    ]
+    row = flr_row(payload)
+    assert flr_status(row).lower() == "mountcompletedsuccessfully"