feat: add movable shader building overlay with touch handling

- Add touch event handling to ShaderBuildingOverlayView for dragging
- Implement boundary constraints to keep overlay within screen bounds
- Add visual feedback with border color changes during dragging
- Add resetPosition() method to restore overlay to default position
- Move ShaderBuildingOverlayView to separate FrameLayout for absolute positioning
- Set container to non-clickable to prevent interference with input controls
- Maintain clickable/focusable state only on the overlay view itself

Signed-off-by: Zephyron <zephyron@citron-emu.org>

src/android/app/src/main/java/org/citron/citron_emu/views/ShaderBuildingOverlayView.kt

@@ -7,6 +7,7 @@ import android.content.Context
 import android.graphics.*
 import android.util.AttributeSet
 import android.util.Log
+import android.view.MotionEvent
 import android.view.View
 import kotlin.math.*
 
@@ -86,6 +87,11 @@ class ShaderBuildingOverlayView @JvmOverloads constructor(
     private var animationProgress: Float = 0f
     private var isAnimating: Boolean = false
 
+    // Touch handling for dragging
+    private var lastTouchX: Float = 0f
+    private var lastTouchY: Float = 0f
+    private var isDragging: Boolean = false
+
     fun updatePerformanceStats(fps: Float, frameTime: Float, speed: Float, shaders: Int) {
         try {
             currentFps = fps
@@ -218,6 +224,50 @@ class ShaderBuildingOverlayView @JvmOverloads constructor(
         drawPerformanceGraph(canvas)
     }
 
+    override fun onTouchEvent(event: MotionEvent): Boolean {
+        when (event.action) {
+            MotionEvent.ACTION_DOWN -> {
+                lastTouchX = event.x
+                lastTouchY = event.y
+                isDragging = true
+                borderPaint.color = Color.parseColor("#FF5722") // Red border when dragging
+                invalidate()
+                return true
+            }
+            MotionEvent.ACTION_MOVE -> {
+                if (isDragging) {
+                    val deltaX = event.x - lastTouchX
+                    val deltaY = event.y - lastTouchY
+
+                    // Update position with boundary constraints
+                    val newX = (x + deltaX).coerceIn(0f, (parent as View).width - width.toFloat())
+                    val newY = (y + deltaY).coerceIn(0f, (parent as View).height - height.toFloat())
+
+                    x = newX
+                    y = newY
+
+                    lastTouchX = event.x
+                    lastTouchY = event.y
+                    invalidate()
+                }
+                return true
+            }
+            MotionEvent.ACTION_UP -> {
+                isDragging = false
+                borderPaint.color = Color.parseColor("#FF9800") // Orange border when not dragging
+                invalidate()
+                return true
+            }
+        }
+        return super.onTouchEvent(event)
+    }
+
+    fun resetPosition() {
+        x = 0f
+        y = 0f
+        invalidate()
+    }
+
     private fun drawPerformanceGraph(canvas: Canvas) {
         if (frameTimeHistory.isEmpty()) return
 

src/android/app/src/main/res/layout/fragment_emulation.xml

@@ -177,17 +177,25 @@
                     android:focusable="false"
                     android:visibility="gone" />
 
+            </LinearLayout>
+
+        </FrameLayout>
+
+        <FrameLayout
+            android:id="@+id/movable_overlay_container"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:clickable="false"
+            android:focusable="false">
+
             <org.citron.citron_emu.views.ShaderBuildingOverlayView
                 android:id="@+id/shader_building_overlay_view"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                    android:layout_marginStart="8dp"
+                android:clickable="true"
-                    android:clickable="false"
+                android:focusable="true"
-                    android:focusable="false"
                 android:visibility="gone" />
 
-            </LinearLayout>
-
         </FrameLayout>
 
     </androidx.coordinatorlayout.widget.CoordinatorLayout>