feat: Improve thermal display and build system

- Replace emoji thermal indicators with modern progress bar UI
- Switch temperature source to battery sensor for better accuracy
- Adjust temperature thresholds (30°C-45°C range)
- Add automatic Vulkan Validation Layer download for Android

The thermal display now shows a visual progress bar with percentage
instead of emojis, making it easier to gauge system temperature at
a glance. Temperature reading now comes from the battery sensor
which is more reliable across devices.

Build system improvements include automated VVL binary downloads
and installation for Android builds when CITRON_DOWNLOAD_ANDROID_VVL
is enabled.

CMakeLists.txt

@@ -117,10 +117,13 @@ if (ANDROID AND YUZU_DOWNLOAD_ANDROID_VVL)
                         WORKING_DIRECTORY "${CMAKE_BINARY_DIR}/externals")
     endif()
 
-    # Copy the arm64 binary to src/android/app/main/jniLibs
+    # Copy the arm64 binary to src/android/app/main/jniLibs only if it doesn't exist
     set(vvl_lib_path "${CMAKE_CURRENT_SOURCE_DIR}/src/android/app/src/main/jniLibs/arm64-v8a/")
-    file(COPY "${CMAKE_BINARY_DIR}/externals/android-binaries-${vvl_version}/arm64-v8a/libVkLayer_khronos_validation.so"
-            DESTINATION "${vvl_lib_path}")
+    set(vvl_lib_file "${vvl_lib_path}/libVkLayer_khronos_validation.so")
+    if (NOT EXISTS "${vvl_lib_file}")
+        file(COPY "${CMAKE_BINARY_DIR}/externals/android-binaries-${vvl_version}/arm64-v8a/libVkLayer_khronos_validation.so"
+                DESTINATION "${vvl_lib_path}")
+    endif()
 endif()
 
 if (ANDROID)

src/android/app/src/main/java/org/yuzu/yuzu_emu/fragments/EmulationFragment.kt

@@ -522,17 +522,57 @@ class EmulationFragment : Fragment(), SurfaceHolder.Callback {
                     !emulationViewModel.isEmulationStopping.value
                 ) {
                     val thermalStatus = when (powerManager.currentThermalStatus) {
-                        PowerManager.THERMAL_STATUS_LIGHT -> "😥"
-                        PowerManager.THERMAL_STATUS_MODERATE -> "🥵"
-                        PowerManager.THERMAL_STATUS_SEVERE -> "🔥"
+                        PowerManager.THERMAL_STATUS_LIGHT -> 0.25f
+                        PowerManager.THERMAL_STATUS_MODERATE -> 0.5f
+                        PowerManager.THERMAL_STATUS_SEVERE -> 0.75f
                         PowerManager.THERMAL_STATUS_CRITICAL,
                         PowerManager.THERMAL_STATUS_EMERGENCY,
-                        PowerManager.THERMAL_STATUS_SHUTDOWN -> "☢️"
-
-                        else -> "🙂"
+                        PowerManager.THERMAL_STATUS_SHUTDOWN -> 1.0f
+                        else -> 0f
                     }
+
+                    // Get temperature from battery thermal sensor
+                    val temperature = try {
+                        val process = Runtime.getRuntime().exec("cat /sys/class/power_supply/battery/temp")
+                        val reader = process.inputStream.bufferedReader()
+                        val temp = reader.readLine().toFloat() / 10f // Convert from decidegrees to degrees
+                        reader.close()
+                        temp
+                    } catch (e: Exception) {
+                        0f
+                    }
+
+                    // Convert to Fahrenheit
+                    val fahrenheit = (temperature * 9f / 5f) + 32f
+
                     if (_binding != null) {
-                        binding.showThermalsText.text = thermalStatus
+                        // Color interpolation based on temperature (green at 30°C, red at 45°C)
+                        val normalizedTemp = ((temperature - 30f) / 15f).coerceIn(0f, 1f)
+                        val red = (normalizedTemp * 255).toInt()
+                        val green = ((1f - normalizedTemp) * 255).toInt()
+                        val color = android.graphics.Color.rgb(red, green, 0)
+
+                        // Create a modern progress bar using block elements
+                        val progressBarLength = 12
+                        val filledBars = (thermalStatus * progressBarLength).toInt()
+                        val progressBar = buildString {
+                            append("│") // Left border
+                            repeat(filledBars) { append("█") }
+                            repeat(progressBarLength - filledBars) { append("░") }
+                            append("│") // Right border
+
+                            // Add percentage
+                            append(" ")
+                            append(String.format("%3d%%", (thermalStatus * 100).toInt()))
+                        }
+
+                        binding.showThermalsText.setTextColor(color)
+                        binding.showThermalsText.text = String.format(
+                            "%s\n%.1f°C • %.1f°F",
+                            progressBar,
+                            temperature,
+                            fahrenheit
+                        )
                     }
                     thermalStatsUpdateHandler.postDelayed(thermalStatsUpdater!!, 1000)
                 }