[Tool] [Windows] Output app path on build completion

[loic-sharma]

⚠️ This re-lands #122858 after it was reverted by #122926. The fix is c098e6f (#122928): it uses CMake's app name instead of pubspec.yaml's app name as these can get out of sync.

Improves the build output:

1. Gives confirmation that the build succeeded
2. Gives the path to the built executable

This matches the behavior of other Flutter platforms like Android.

Part of #120127

Flutter run

> flutter run -d windows
Launching lib\main.dart on Windows in debug mode...
Building Windows application...                                    11.1s
✓  Built build\windows\runner\Debug\x10.exe.
Syncing files to device Windows...                                  60ms

Flutter run key commands.
r Hot reload. 🔥🔥🔥
R Hot restart.
h List all available interactive commands.
d Detach (terminate "flutter run" but leave application running).
c Clear the screen
q Quit (terminate the application on the device).

Flutter build

> flutter build windows
Building Windows application...                                    25.9s
✓  Built build\windows\runner\Release\x10.exe (0.1MB).

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

[loic-sharma]

This is the reland's fix. The original change used the app's name according to the pubspec.yaml file and assumed that matched CMake's app name. However, these files can get out of sync.

[christopherfujino]

LGTM

[cbracken]

🎉