fix(release): preserve attribution placement; default update notifs to o

- Move What's Changed/New Contributors before Installation in release notes
- Preserve committed attribution when regenerating via writeReleaseNotesForVersion
- Change notificationType default from 'both' to 'overlay' for new installs

src/config/config.test.ts

@@ -153,7 +153,7 @@ test('loads defaults when config is missing', () => {
   assert.equal(config.stats.autoOpenBrowser, false);
   assert.equal(config.updates.enabled, true);
   assert.equal(config.updates.checkIntervalHours, 24);
-  assert.equal(config.updates.notificationType, 'both');
+  assert.equal(config.updates.notificationType, 'overlay');
   assert.equal(config.updates.channel, 'stable');
   assert.equal(config.mpv.socketPath, DEFAULT_CONFIG.mpv.socketPath);
   assert.equal(config.mpv.backend, 'auto');
@@ -2814,7 +2814,7 @@ test('template generator includes known keys', () => {
   );
   assert.match(
     output,
-    /"notificationType": "both",? \/\/ How SubMiner announces available updates\..*Values: overlay \| system \| both \| none \| osd \| osd-system/,
+    /"notificationType": "overlay",? \/\/ How SubMiner announces available updates\..*Values: overlay \| system \| both \| none \| osd \| osd-system/,
   );
   assert.match(
     output,

src/config/definitions/defaults-core.ts

@@ -128,7 +128,7 @@ export const CORE_DEFAULT_CONFIG: Pick<
   updates: {
     enabled: true,
     checkIntervalHours: 24,
-    notificationType: 'both',
+    notificationType: 'overlay',
     channel: 'stable',
   },
   notifications: {