test(compaction): initialize anti-thrash fixture state

tests/agent/test_compress_focus.py

@@ -23,6 +23,8 @@ def _make_compressor():
     compressor.compression_count = 0
     compressor.last_prompt_tokens = 0
     compressor._previous_summary = None
+    compressor._ineffective_compression_count = 0
+    compressor._verify_compaction_cleared_threshold = False
     compressor._summary_failure_cooldown_until = 0.0
     compressor.summary_model = None
     compressor.model = "test-model"