Fix Settings UI reactivity, resolve compiler warnings, update .gitignore

- Make screen capture permission and battery optimization states reactive
- Add lifecycle observer to refresh battery status on resume
- Add lifecycle-runtime-compose dependency for non-deprecated LocalLifecycleOwner
- Replace deprecated LocalLifecycleOwner import
- Remove unused REQUEST_CODE constant
- Use KTX createBitmap() and bitmap[x,y] extensions
- Add misc.xml and junie.xml to .gitignore

android/.idea/misc.xml

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="temurin-21" project-jdk-type="JavaSDK">
-    <output url="file://$PROJECT_DIR$/build/classes" />
-  </component>
-  <component name="ProjectType">
-    <option name="id" value="Android" />
-  </component>
-</project>