feat: add configurable drag speed and delay

Added new features to drag functionality:
- Added startDelay parameter to specify delay before drag movement
- Added dragSpeed parameter to control movement speed
- Updated documentation in both English and Chinese

This allows users to fine-tune both the timing and speed of drag movements.

Author: w4po

QtScrcpy/QtScrcpyCore

@@ -60,6 +60,8 @@ Description of the unique attributes of different key mapping types:
     -key The key code to be mapped
     -startPos Simulate the start position of touch drag
     -endPos Simulate the end position of touch drag
+    -dragSpeed Speed of the drag movement (range 0-1, default 1.0). Higher values result in faster movements
+    -startDelay Optional delay in milliseconds to wait after the initial touch before starting the drag movement
 
 -KMT_STEER_WHEEL
     -centerPos steering wheel center point

docs/KeyMapDes.md

@@ -60,6 +60,8 @@
     - key 要映射的按键码
     - startPos 模拟触摸拖动的开始位置
     - endPos 模拟触摸拖动的结束位置
+    - dragSpeed 拖动移动的速度（范围0-1，默认1.0）。数值越大，移动越快
+    - startDelay 可选的延迟时间（毫秒），在开始拖动移动之前等待指定的时间
 
 - KMT_STEER_WHEEL
     - centerPos 方向盘中心点
@@ -72,5 +74,3 @@
     - upOffset 按下上方向键后模拟拖动到相对centerPos位置水平偏上upOffset处
     - downOffset 按下下方向键后模拟拖动到相对centerPos位置水平偏下downOffset处
 
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