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.

rally.py

@@ -0,0 +1,99 @@
+"""Logitech Rally Camera V-R0010 + Dante room mic (speaker identity)."""
+from __future__ import annotations
+
+import logging
+import re
+from pathlib import Path
+
+from discovery import Camera
+from usb_ids import (
+    RALLY_IDENTITY,
+    is_rally_pid,
+    looks_like_rally_name,
+    usb_vid_pid_of_video_node,
+)
+
+log = logging.getLogger("cameras.rally")
+
+_CARD_RE = re.compile(r"\s*(\d+)\s+\[([A-Za-z0-9_]+)\s*\]:\s*(.*)")
+
+
+def dante_capture_card() -> int | None:
+    """ALSA card index for the Audinate Dante USB I/O module, if present."""
+    path = Path("/proc/asound/cards")
+    if not path.is_file():
+        return None
+    for line in path.read_text().splitlines():
+        m = _CARD_RE.match(line)
+        if not m:
+            continue
+        rest = (m.group(3) or "").lower()
+        name = (m.group(2) or "").lower()
+        if "dante" in rest or "dante" in name:
+            return int(m.group(1))
+    return None
+
+
+def rally_video_node() -> str | None:
+    pinned = Path("/dev/rally")
+    if pinned.exists():
+        return str(pinned)
+    sysfs = Path("/sys/class/video4linux")
+    if not sysfs.is_dir():
+        return None
+    for p in sorted(sysfs.glob("video*"), key=lambda x: int(x.name[5:] or 0)):
+        name = (p / "name").read_text().strip() if (p / "name").is_file() else ""
+        idx = (p / "index").read_text().strip() if (p / "index").is_file() else ""
+        node = f"/dev/{p.name}"
+        if idx != "0":
+            continue
+        if looks_like_rally_name(name):
+            return node
+        ids = usb_vid_pid_of_video_node(node)
+        if ids is not None and is_rally_pid(ids[1]):
+            return node
+    return None
+
+
+def _serial_of_video(node: str) -> str:
+    link = Path(f"/sys/class/video4linux/{Path(node).name}/device")
+    try:
+        p = link.resolve()
+    except OSError:
+        return ""
+    for _ in range(12):
+        cand = p / "serial"
+        if cand.is_file():
+            return cand.read_text().strip()
+        if str(p).startswith("/sys/devices"):
+            p = p.parent
+        else:
+            break
+    return ""
+
+
+def discover_rally(*, width: int = 1920, height: int = 1080) -> Camera | None:
+    """Speaker camera: Rally UVC + Dante capture. None if the head is missing."""
+    video = rally_video_node()
+    if not video:
+        return None
+    card = dante_capture_card()
+    serial = _serial_of_video(video)
+    cam = Camera(
+        index=20,
+        identity=RALLY_IDENTITY,
+        video_device=video,
+        audio_card=card,
+        serial=serial,
+        width=width,
+        height=height,
+    )
+    log.info(
+        "rally video=%s audio=%s serial=%s %dx%d",
+        video,
+        f"hw:{card},0" if card is not None else "none",
+        serial or "-",
+        width,
+        height,
+    )
+    return cam