test: no test throws a response away; the stream session is narrowed, not baselined

The 7 baselined Optional accesses in plex/stream.py were one fact the type did not carry: the
initial spawn (replace_only=None) always supersedes, so only the fallback respawn can get None.
An assert at the call site says so; the pyright baseline drops 195 -> 188.

test_abuse_limits: the public-URL and YouTube enqueue tests stopped at the profile lookup
(400 no_profile) and passed on that unrelated refusal. They now send an inline spec and assert
the job is queued. The same shape — a request whose response is discarded — sat at 53 more
places across the suite (all returned what they should, measured with a TestClient probe);
each now asserts its status, and test_response_checked keeps it that way (seen red).

backend/tests/test_email_canonical.py

@@ -334,7 +334,7 @@ def test_me_reports_the_google_address_only_when_it_differs(client, db, make_use
     )
     assert client.get("/api/me").json()["google_email"] is None
 
-    client.post("/auth/logout")
+    assert client.post("/auth/logout").status_code == 200
     tagged = make_user(email="me+siftlode@gmail.com", password=_UAT_PW)
     tagged.google_email = "me@gmail.com"
     db.commit()