Merge pull request #1865 from tangzz-radxa/docs/q8b-hw-design-v1-30-20260622

docs(q8b/download): add Hardware Design section with v1.30 schematic and placement map

Author: Milir-Radxa

docs/dragon/q8b/download.md

@@ -31,3 +31,9 @@ Dragon Q8B 出厂默认烧录 SPI 启动固件，正常情况下无需烧录启
 
 - SPI 启动固件（BIOS）
   - [启动固件（BIOS）](https://dl.radxa.com/dragon/q8b/images/)
+
+## 硬件设计
+
+- [位号图 V1.30](https://dl.radxa.com/dragon/q8b/hw/radxa_dragon_q8b_components_placement_map_v1.30.pdf)
+
+- [原理图 V1.30](https://dl.radxa.com/dragon/q8b/hw/radxa_dragon_q8b_schematic_v1.30.pdf)

i18n/en/docusaurus-plugin-content-docs/current/dragon/q8b/download.md

@@ -31,3 +31,9 @@ Dragon Q8B ships with SPI boot firmware preinstalled. Normally you do not need t
 
 - SPI Boot Firmware (BIOS)
   - [Boot Firmware (BIOS)](https://dl.radxa.com/dragon/q8b/images/)
+
+## Hardware Design
+
+- [Component Placement Diagram V1.30](https://dl.radxa.com/dragon/q8b/hw/radxa_dragon_q8b_components_placement_map_v1.30.pdf)
+
+- [Schematic V1.30](https://dl.radxa.com/dragon/q8b/hw/radxa_dragon_q8b_schematic_v1.30.pdf)