Document iOS camera motion sensor, camera stream and kiosk wake on motion

[bemble]

Document iOS camera motion sensor, camera stream, and kiosk wake on camera motion

Documents the features added in home-assistant/iOS#5140:

docs/core/sensors.md

• Adds binary_sensor.camera_motion and sensor.camera_stream to the iOS sensor list.
• New "Camera motion sensor" section: front-camera motion detection, disabled by default (camera permission and green indicator called out), settings (frame rate, changed area threshold, clear delay) with defaults and the performance/heat trade-off, and the attributes table.
• New "Camera stream sensor" section: the sensor reports the stream status (streaming/idle); the stream itself runs a small MJPEG server on the device, enabled by turning the sensor on. Includes how to add it to Home Assistant with the MJPEG camera integration using the Stream URL attribute, the optional Basic auth credentials, and the same-network/DHCP-reservation guidance.

docs/integrations/ios-kiosk-mode.md

• New Wake on camera motion screensaver option: motion counts as activity — the screensaver doesn't start while motion is detected, is dismissed by motion, and the inactivity timer restarts after the motion clear delay.
• A tip suggesting Guided Access for truly dedicated displays, since kiosk mode can't prevent leaving the app.

No screenshots: the new UI follows the existing sensor-settings and kiosk-settings screens already pictured on these pages.

[home-assistant]

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