feat(logging): add runtime log levels and debug log export (#241)

Add a System setting for Off/Normal/Debug logging, apply readable local timestamps to backend logs, and enable exporting buffered runtime logs to a file when debug mode is active.

Co-authored-by: Maxim Isaev <im@friclub.ru>

src/locales/en.ts

@@ -666,6 +666,14 @@ export const enTranslation = {
     tabServer: 'Server',
     tabUsers: 'Users',
     tabSystem: 'System',
+    loggingTitle: 'Logging',
+    loggingModeDesc: 'Controls backend log verbosity in the terminal.',
+    loggingModeOff: 'Off',
+    loggingModeNormal: 'Normal',
+    loggingModeDebug: 'Debug',
+    loggingExport: 'Export logs',
+    loggingExportSuccess: 'Logs exported ({{count}} lines).',
+    loggingExportError: 'Could not export logs.',
     tabGeneral: 'General',
     ratingsSectionTitle: 'Ratings',
     ratingsSkipStarTitle: 'Skip for 1 star',