regenerate jpeg encoder (#1198)

* regenerate jpeg encoder

* add README to gif/jpeg

* 开机启动显示开发板信息，提前启动event loop

main/display/lvgl_display/jpg/README.md

@@ -0,0 +1,17 @@
+# 说明 / Description
+
+## 中文
+
+本目录代码移植自 https://github.com/espressif/esp32-camera/blob/master/conversions/jpge.cpp
+
+由于原版本使用了 8KB 静态全局变量，会导致程序加载后长期占用 SRAM。
+
+本版本改为类成员变量，仅在使用时从堆内存申请，代码由 Cursor 重新生成。
+
+## English
+
+The code in this directory is ported from https://github.com/espressif/esp32-camera/blob/master/conversions/jpge.cpp
+
+The original version used 8KB static global variables, which would cause long-term SRAM occupation after program loading.
+
+This version has been changed to class member variables, which are only allocated from heap memory when in use. The code has been regenerated by Cursor.