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.

annexb.py

@@ -0,0 +1,72 @@
+"""Split Annex-B H.264 into access units."""
+from __future__ import annotations
+
+
+def _start_at(buf: bytes, i: int) -> int:
+    n = len(buf)
+    while i + 2 < n:
+        if buf[i] == 0 and buf[i + 1] == 0:
+            if buf[i + 2] == 1:
+                return i
+            if i + 3 < n and buf[i + 2] == 0 and buf[i + 3] == 1:
+                return i
+        i += 1
+    return -1
+
+
+def nal_unit_type(nal: bytes) -> int:
+    """First NAL type in an AU (5 = IDR)."""
+    i = _start_at(nal, 0)
+    if i < 0:
+        return 0
+    hdr = i + (4 if i + 3 < len(nal) and nal[i + 2] == 0 else 3)
+    if hdr >= len(nal):
+        return 0
+    return nal[hdr] & 0x1F
+
+
+def is_keyframe(au: bytes) -> bool:
+    i = 0
+    n = len(au)
+    while True:
+        s = _start_at(au, i)
+        if s < 0:
+            return False
+        hdr = s + (4 if s + 3 < n and au[s + 2] == 0 else 3)
+        if hdr >= n:
+            return False
+        ntype = au[hdr] & 0x1F
+        if ntype == 5:
+            return True
+        i = hdr + 1
+
+
+class AnnexBSplitter:
+    """Feed byte-stream; yield complete AUs (including start codes)."""
+
+    def __init__(self) -> None:
+        self._buf = bytearray()
+
+    def push(self, data: bytes) -> list[bytes]:
+        if data:
+            self._buf.extend(data)
+        out: list[bytes] = []
+        buf = self._buf
+        first = _start_at(bytes(buf), 0)
+        if first < 0:
+            if len(buf) > 1_000_000:
+                del buf[: len(buf) - 8]
+            return out
+        if first:
+            del buf[:first]
+        pos = 0
+        while True:
+            nxt = _start_at(bytes(buf), pos + 3)
+            if nxt < 0:
+                break
+            au = bytes(buf[:nxt])
+            if au:
+                out.append(au)
+            del buf[:nxt]
+            pos = 0
+        return out