(feat) add workflows for flutter

Author: BirjuVachhani

specs/flutter/flutter_build_runner_build.yaml

@@ -0,0 +1,10 @@
+--- 
+name: Run Build Ruuner 
+command: "flutter pub run build_runner build --delete-conflicting-outputs" 
+tags:
+  - flutter
+description: Run build runner to generate code-gen for flutter project.
+source_url: "https://pub.dev/packages/build_runner" 
+author: Birju Vachhani
+author_url: "https://github.com/BirjuVachhani"
+shells: []

specs/flutter/flutter_build_runner_watch.yaml

@@ -0,0 +1,10 @@
+--- 
+name: Run Build Ruuner Watch
+command: "flutter pub run build_runner watch --delete-conflicting-outputs" 
+tags:
+  - flutter
+description: Run build runner to generate code-gen for flutter project when files changes.
+source_url: "https://pub.dev/packages/build_runner" 
+author: Birju Vachhani
+author_url: "https://github.com/BirjuVachhani"
+shells: []

specs/flutter/flutter_clean_project.yaml

@@ -0,0 +1,10 @@
+--- 
+name: Clean Project
+command: "flutter clean && flutter pub get" 
+tags:
+  - flutter
+description: Cleans flutter project and gets dependencies to make project ready for a fresh run.
+source_url: "https://docs.flutter.dev/reference/flutter-cli" 
+author: Birju Vachhani
+author_url: "https://github.com/BirjuVachhani"
+shells: []