Add a checkbox to enable file logging from the UI, in developer settings.

Fixes issue #20372.

The file is written to PSP/SYSTEM/DUMP/log.txt by default, but you can
override from the command line if needed.

assets/lang/de_DE.ini

@@ -326,6 +326,7 @@ Jit Compare = JIT-Vergleich
 JIT debug tools = JIT-Fehlerbehebungs-Werkzeuge
 Log Dropped Frame Statistics = Statistik für fehlende Einzelbilder protokollieren
 Log Level = Protokollierungsstufe
+Log to file = Log to file
 Log View = Protokollansicht
 Logging Channels = Protkollkanäle
 Multi-threaded rendering = Multi-threaded rendering