TF-4269 Fix Sentry release version sync across platforms

Use --dart-define=SENTRY_RELEASE=<full-tag> in Fastlane so the app
reports the same version string to Sentry as CI uses when uploading
symbols, bypassing iOS CFBundleShortVersionString stripping.

- Android Fastfile: add --dart-define=SENTRY_RELEASE (build-name unchanged)
- iOS Fastfile: pass DART_DEFINES via xcargs (increment_version_number unchanged)
- Dart: read SENTRY_RELEASE dart-define first, fall back to PackageInfo.version
- NSE/Web unaffected: NSE reads from Keychain, Web falls back to PackageInfo

lib/features/mailbox_dashboard/domain/linagora_ecosystem/sentry_config_linagora_ecosystem.dart

@@ -41,12 +41,15 @@ class SentryConfigLinagoraEcosystem extends LinagoraEcosystemProperties {
 
 extension SentryConfigLinagoraEcosystemExtension on SentryConfigLinagoraEcosystem {
   Future<SentryConfig> toSentryConfig() async {
-    final appVersion = await ApplicationManager().getAppVersion();
+    const dartDefineRelease = String.fromEnvironment('SENTRY_RELEASE');
+    final release = dartDefineRelease.isNotEmpty
+        ? dartDefineRelease
+        : await ApplicationManager().getAppVersion();
 
     return SentryConfig(
       dsn: dsn ?? '',
       environment: environment ?? '',
-      release: appVersion,
+      release: release,
       isAvailable: enabled ?? false,
     );
   }