feat: point the fleet at wss LiveKit room uwh-telhai

Publish and subscribe over wss://livekit.uni-wh.de:7800 and refuse
cleartext ws://. Conference room is uwh-telhai. Includes the uncommitted
encoded H.264 publish path, Rally hairpin, and KMS wall overlay.

tests/test_nal_shm.py

@@ -0,0 +1,46 @@
+"""Latest-AU H.264 mmap: overwrite unread payloads; seq is monotonic."""
+from nal_shm import AU_MAX, NalReader, NalWriter
+
+
+def test_writer_seq_starts_at_one_and_increments(tmp_path):
+    path = str(tmp_path / "cam-01.h264")
+    w = NalWriter(path, max_payload=64)
+    assert w.write(b"\x00\x00\x00\x01\x65" + b"x" * 10) == 1
+    assert w.write(b"\x00\x00\x00\x01\x41" + b"y" * 10) == 2
+    w.close()
+
+
+def test_reader_returns_latest_payload(tmp_path):
+    path = str(tmp_path / "cam-01.h264")
+    w = NalWriter(path, max_payload=64)
+    w.write(b"first-access-unit-xxxx")
+    w.write(b"second-access-unit-yyy")
+    r = NalReader(path)
+    seq, payload = r.read()
+    assert seq == 2
+    assert payload.startswith(b"second-access-unit")
+    w.close()
+    r.close()
+
+
+def test_reader_none_when_no_new_au(tmp_path):
+    path = str(tmp_path / "cam-01.h264")
+    w = NalWriter(path, max_payload=64)
+    w.write(b"only-once")
+    r = NalReader(path)
+    assert r.read()[0] == 1
+    assert r.read() is None
+    w.close()
+    r.close()
+
+
+def test_write_drops_oversize_payload(tmp_path):
+    path = str(tmp_path / "cam-01.h264")
+    w = NalWriter(path, max_payload=8)
+    assert w.write(b"123456789") == 0
+    w.close()
+
+
+def test_au_max_is_bounded():
+    assert AU_MAX >= 64 * 1024
+    assert AU_MAX <= 2 * 1024 * 1024