feat(perception): preserve resident runtime across recoverable input gaps

tests/test_perception_streaming_decoder.py

@@ -162,6 +162,22 @@ def fake_av(monkeypatch):
     return codec, av, opens
 
 
+def test_epoch_reset_discards_predictive_state_but_keeps_decoder_object(fake_av):
+    decoder = decoder_module.FragmentDecoder()
+    init, frame = fixture()
+    decoder.configure(init)
+    decoder.decode(frame)
+    decoder.reset(init)
+    assert decoder.frames == 0 and decoder._next_dts is None
+    decoder.decode(fixture(dts=500)[1])
+    assert decoder.frames == 1 and decoder._next_dts == 600
+    decoder.reset(init)
+    with pytest.raises(decoder_module.StreamingDecodeError, match="random-access"):
+        decoder.decode(fixture(dts=600, sync=False)[1])
+    with pytest.raises(decoder_module.StreamingDecodeError, match="failed decoder"):
+        decoder.reset(init)
+
+
 def test_persistent_codec_emits_current_frame_without_demux_or_flush(fake_av):
     codec, _, opens = fake_av
     init, fragment = fixture()