feat: add draggable FAB and fix system UI visibility

- Make FAB truly draggable with detectDragGestures
- Add screen bounds checking to keep FAB visible
- Hide navigation bar and status bar for immersive overlay experience
- Support both Android R+ (WindowInsetsController) and legacy system UI flags
- FAB now floats anywhere on screen and can be repositioned by dragging

Fixes: Navigation bar and status bar no longer show during capture mode
Fixes: FAB is now truly floating and user can position it anywhere

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/src/main/java/com/quillstudios/pokegoalshelper/ui/FloatingUIActivity.kt

@@ -20,6 +20,12 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.rotate
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.input.pointer.pointerInput
+import androidx.compose.foundation.gestures.detectDragGestures
+import androidx.compose.ui.platform.LocalConfiguration
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.IntOffset
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.hapticfeedback.HapticFeedbackType
@@ -95,8 +101,28 @@ class FloatingUIActivity : ComponentActivity() {
     }
     
     private fun setupTransparentOverlay() {
-        // Make the activity transparent
+        // Make the activity transparent and fullscreen
         window.apply {
+            // Hide system UI (navigation bar, status bar)
+            if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.R) {
+                setDecorFitsSystemWindows(false)
+                insetsController?.let { controller ->
+                    controller.hide(android.view.WindowInsets.Type.systemBars())
+                    controller.systemBarsBehavior = android.view.WindowInsetsController.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE
+                }
+            } else {
+                @Suppress("DEPRECATION")
+                decorView.systemUiVisibility = (
+                    android.view.View.SYSTEM_UI_FLAG_LAYOUT_STABLE
+                    or android.view.View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
+                    or android.view.View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
+                    or android.view.View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
+                    or android.view.View.SYSTEM_UI_FLAG_FULLSCREEN
+                    or android.view.View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
+                )
+            }
+            
+            // Make it show over other apps
             setFlags(
                 WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL,
                 WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
@@ -106,7 +132,6 @@ class FloatingUIActivity : ComponentActivity() {
                 WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
             )
             
-            // Make it show over other apps
             if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
                 setType(WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY)
             } else {
@@ -150,20 +175,36 @@ fun FloatingFABInterface(
     var isProcessing by remember { mutableStateOf(false) }
     val hapticFeedback = LocalHapticFeedback.current
     
+    // Draggable position state
+    var fabOffset by remember { mutableStateOf(Offset.Zero) }
+    val configuration = LocalConfiguration.current
+    val density = LocalDensity.current
+    
+    // Calculate screen bounds for FAB positioning
+    val screenWidth = with(density) { configuration.screenWidthDp.dp.toPx() }
+    val screenHeight = with(density) { configuration.screenHeightDp.dp.toPx() }
+    val fabSize = with(density) { 56.dp.toPx() }
+    
     Box(
         modifier = Modifier
             .fillMaxSize()
-            .background(Color.Transparent),
-        contentAlignment = Alignment.BottomEnd
+            .background(Color.Transparent)
     ) {
         // Main content area - transparent to allow touches through
         Spacer(modifier = Modifier.fillMaxSize())
         
-        // FAB and menu area
+        // FAB and menu area - positioned with offset
         Column(
             horizontalAlignment = Alignment.End,
             verticalArrangement = Arrangement.Bottom,
-            modifier = Modifier.padding(16.dp)
+            modifier = Modifier
+                .offset { 
+                    IntOffset(
+                        fabOffset.x.toInt(),
+                        fabOffset.y.toInt()
+                    )
+                }
+                .padding(16.dp)
         ) {
             
             // Expanded Menu Items
@@ -213,7 +254,7 @@ fun FloatingFABInterface(
                     )
                     
                     MenuFABItem(
-                        icon = Icons.Default.RadioButtonUnchecked,
+                        icon = Icons.Default.AccountCircle,
                         label = "POKEBALL",
                         containerColor = MaterialTheme.colorScheme.error,
                         onClick = {
@@ -263,6 +304,19 @@ fun FloatingFABInterface(
                 onLongClick = {
                     hapticFeedback.performHapticFeedback(HapticFeedbackType.LongPress)
                     onClose()
+                },
+                onDrag = { dragAmount ->
+                    val newOffset = Offset(
+                        (fabOffset.x + dragAmount.x).coerceIn(
+                            -screenWidth + fabSize, 
+                            0f
+                        ),
+                        (fabOffset.y + dragAmount.y).coerceIn(
+                            -screenHeight + fabSize,
+                            0f
+                        )
+                    )
+                    fabOffset = newOffset
                 }
             )
         }
@@ -274,7 +328,8 @@ fun MainFloatingActionButton(
     isProcessing: Boolean,
     isMenuExpanded: Boolean,
     onClick: () -> Unit,
-    onLongClick: () -> Unit
+    onLongClick: () -> Unit,
+    onDrag: (Offset) -> Unit
 ) {
     val rotation by animateFloatAsState(
         targetValue = if (isMenuExpanded) 45f else 0f,
@@ -295,7 +350,20 @@ fun MainFloatingActionButton(
         onClick = onClick,
         modifier = Modifier
             .size(56.dp)
-            .rotate(if (isProcessing) processingRotation else rotation),
+            .rotate(if (isProcessing) processingRotation else rotation)
+            .pointerInput(Unit) {
+                detectDragGestures(
+                    onDragStart = {
+                        // Provide haptic feedback when drag starts
+                    },
+                    onDragEnd = {
+                        // Optional: snap to screen edges
+                    },
+                    onDrag = { _, dragAmount ->
+                        onDrag(dragAmount)
+                    }
+                )
+            },
         containerColor = when {
             isProcessing -> MaterialTheme.colorScheme.tertiary
             isMenuExpanded -> MaterialTheme.colorScheme.error
@@ -310,7 +378,7 @@ fun MainFloatingActionButton(
             imageVector = when {
                 isProcessing -> Icons.Default.Refresh
                 isMenuExpanded -> Icons.Default.Close
-                else -> Icons.Default.Camera
+                else -> Icons.Default.Home
             },
             contentDescription = when {
                 isProcessing -> "Processing..."