[bug]: upload symbols fail on macos when Swift Package Manager is enabled

### Is there an existing issue for this?

- [x] I have searched the existing issues.

### CLI Version

1.3.1

### Firebase Tools version

13.29.1

### Flutter Doctor Output

```
[✓] Flutter (Channel stable, 3.41.4, on macOS 15.7.3 24G419 darwin-arm64, locale en-CA) [676ms]
• Flutter version 3.41.4 on channel stable at ***
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision ff37bef603 (6 days ago), 2026-03-03 16:03:22 -0800
• Engine revision e4b8dca3f1
• Dart version 3.11.1
• DevTools version 2.54.1
• Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android, enable-ios, no-cli-animations,
enable-native-assets, enable-swift-package-manager, omit-legacy-version-file, enable-lldb-debugging, enable-uiscene-migration

[✓] Xcode - develop for iOS and macOS (Xcode 26.2) [1,264ms]
• Xcode at /Applications/Xcode_26.2.app/Contents/Developer
• Build 17C52
• CocoaPods version 1.16.2

[✓] Connected device (3 available) [6.9s]
• macOS (desktop) • macos • darwin-arm64 • macOS 15.7.3 24G419 darwin-arm64

[✓] Network resources [234ms]
• All expected network resources are available.

• No issues found!
```

### Description

After enabling the Swift Package Manager on MacOS using following config in pubspec.yaml

```
flutter:
config:
enable-swift-package-manager: true
```

The macos target build is failing with the following error:

```
ProcessException: No such file or directory
Command: /Users/***/Documents/Projects/***/build/macos/Build/Products/SourcePackages/checkouts/firebase-ios-sdk/Crashlytics/run --validate --flutter-project /Users/***/Documents/Projects/***/.dart_tool/flutterfire/platforms/macos/default/***/app_id_file.json
```

This does not seem to be the same as #392 because I see the `run` script is actually located at:

```
/Users/***/Documents/Projects/***/build/macos/SourcePackages/checkouts/firebase-ios-sdk/Crashlytics/run
```

### Steps to reproduce

You should see the same issue with `firebase_crashlytics` example app, just enable swift package manager and run macos target.

https://github.com/firebase/flutterfire/tree/main/packages/firebase_crashlytics/firebase_crashlytics/example

### Expected behavior

Should be able to upload dSYMs when building macos target

### Screenshots

_No response_

### Additional context and comments

_No response_