fix(settings): accept omitted optional values after upgrades

Restore the v2.0.35 renderer settings validation behavior that was lost when the download path returned to the v2.0.28 baseline. Ignore undefined optional values at top level and inside structured settings while continuing to reject unknown concrete keys and invalid types. Cover a full settings save containing a Real-Debrid account status without the optional email field, plus obsolete optional-field handling.

src/main/renderer-settings.ts

@@ -30,7 +30,11 @@ function validateJsonValue(value: unknown, depth = 0): void {
   }
   const entries = Object.entries(value as Record<string, unknown>);
   if (entries.length > 10_000) invalid();
-  entries.forEach(([, entry]) => validateJsonValue(entry, depth + 1));
+  entries.forEach(([, entry]) => {
+    if (entry !== undefined) {
+      validateJsonValue(entry, depth + 1);
+    }
+  });
 }
 
 function validateTopLevelType(value: unknown, expected: unknown): void {
@@ -64,6 +68,9 @@ export function validateRendererSettingsUpdate(value: unknown, current: AppSetti
   const input = value as Record<string, unknown>;
   const output: Record<string, unknown> = {};
   for (const [key, entry] of Object.entries(input)) {
+    if (entry === undefined) {
+      continue;
+    }
     if (DERIVED_KEYS.has(key)) {
       continue;
     }