[Doc][2/N] Reorganize Models and Usage sections (#11755)

Signed-off-by: DarkLight1337 <tlleungac@connect.ust.hk>

docs/source/features/quantization/index.md

@@ -0,0 +1,19 @@
+(quantization-index)=
+
+# Quantization
+
+Quantization trades off model precision for smaller memory footprint, allowing large models to be run on a wider range of devices.
+
+```{toctree}
+:caption: Contents
+:maxdepth: 1
+
+supported_hardware
+auto_awq
+bnb
+gguf
+int8
+fp8
+fp8_e5m2_kvcache
+fp8_e4m3_kvcache
+```