optimized avatar and linkify performance, refined navigation to preserve popups, implemented read marker caching, and added file size limits for saving, minor timetable details changes

lib/view/pages/settings/sections/about_section.dart

@@ -67,12 +67,12 @@ class AboutSection extends StatelessWidget {
       applicationIcon: const Icon(Icons.apps),
       applicationName: 'MarianumMobile',
       applicationVersion:
-          '${appInfo.appName}\n\nPackage: ${appInfo.packageName}\nVersion: ${appInfo.version}\nBuild: ${appInfo.buildNumber}',
+          '${appInfo.appName}\n\n${appInfo.packageName}\nVersion: ${appInfo.version}\nBuild/Relase-nummer: ${appInfo.buildNumber}',
       applicationLegalese:
           'Dies ist ein Inoffizieller Marianum-Cloud & Webuntis Client und wird nicht vom Marianum selbst betrieben.\n'
           'Keinerlei Gewähr für Vollständigkeit, Richtigkeit und Aktualität!\n\n'
-          "${kReleaseMode ? "Production" : "Development"} build\n"
-          'Marianum Fulda 2023-${Jiffy.now().year}\nElias Müller',
+          "${kReleaseMode ? "Production" : "Development ${kProfileMode ? "(Profiling)" : "(Debug)"}"} build.\n\n"
+          'Marianum Fulda 2019-2020, 2023-${Jiffy.now().year}\nElias Müller',
     );
   }
 
@@ -92,7 +92,7 @@ class AboutSection extends StatelessWidget {
       ),
       ListTile(
         leading: const CenteredLeading(Icon(Icons.date_range_outlined)),
-        title: const Text('Infos zu Web-/ Untis'),
+        title: const Text('Infos zu (Web) Untis'),
         subtitle: const Text('Für den Stundenplan'),
         trailing: const Icon(Icons.arrow_right),
         onTap: () => PrivacyInfo(
@@ -106,7 +106,7 @@ class AboutSection extends StatelessWidget {
           Icon(Icons.send_time_extension_outlined),
         ),
         title: const Text('Infos zu mhsl'),
-        subtitle: const Text('Für Countdowns, Marianum Message und mehr'),
+        subtitle: const Text('Für Push, Kalendertermine, Marianum Message und mehr'),
         trailing: const Icon(Icons.arrow_right),
         onTap: () => PrivacyInfo(
           providerText: 'mhsl',