Add Jetson-specific Gstreamer guide for real-time video processing (#232)

Adds a comprehensive guide for implementing low-latency video pipelines on NVIDIA Jetson using GStreamer. Covers zero-copy NVMM architecture to bypass CPU bottlenecks, optimized configurations for CSI and V4L2 sensors, and hardware-accelerated H.264 encoding for UDP/RTP streaming. Includes implementation examples for custom CUDA processing via nvivafilter and integration with Python and C++. 

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Co-authored-by: jaswu51 <506346013@qq.com>
Co-authored-by: Nevin Valsaraj <nevin.valsaraj32@gmail.com>

Author: 3 people

_data/navigation.yml

@@ -248,6 +248,8 @@ wiki:
         url: /wiki/networking/ros-distributed/
       - title: Setting up WiFi hotspot at the boot up for Linux devices
         url: /wiki/networking/wifi-hotspot/
+      - title: Real-Time Video Processing on Jetson with GStreamer
+        url: /wiki/networking/gstreamer-jetson-realtime-video/
   - title: Simulation
     url: /wiki/simulation/
     children: