Add language scaffolding: manifest, gitignore, editorconfig

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013kj58Jugkic783b8ZrtTVZ

.editorconfig

@@ -0,0 +1,17 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+
+[*.{rs,toml}]
+indent_size = 4
+
+[*.{py,dart,json,yaml,yml}]
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false

.gitignore

@@ -0,0 +1,12 @@
+.dart_tool/
+.packages
+build/
+.flutter-plugins
+.flutter-plugins-dependencies
+*.iml
+.idea/
+android/.gradle/
+android/local.properties
+ios/Pods/
+
+# pubspec.lock IS committed: this is an application, not a package.