test(gateway): drop the stale restore-path section from the salvaged test module

tests/gateway/test_transcript_read_failure_100788.py

@@ -14,9 +14,9 @@ model happily answered as if nothing had ever been discussed.
 Two guarantees under test:
   A. ``load_transcript`` raises ``TranscriptReadError`` on a read failure,
      while a genuinely empty session still returns ``[]``.
-  B. The gateway restore path degrades loudly: history stays empty, and a
-     per-turn ephemeral notice is queued telling the model the history
-     exists but is unreadable.
+  B. Slash-command handlers that read the transcript reply with
+     ``HISTORY_UNREADABLE`` instead of raising into the dispatch wrapper
+     (which logs and sends nothing).
 
 Offline: SQLite on tmp_path only, no network.
 """
@@ -74,11 +74,6 @@ class TestLoadTranscriptReadFailure:
         assert store.load_transcript("nope") == []
 
 
-# --------------------------------------------------------------------------
-# B. restore path: empty history + a degraded-history notice
-# --------------------------------------------------------------------------
-
-
 # --------------------------------------------------------------------------
 # B. slash-command handlers surface the failure instead of dying silently.
 #    Before: the handler raised, base.py's dispatch wrapper logged