chore(repo): initialise le dépôt git et l'état de configuration IdeA

Ajoute le .gitignore Flutter/Dart standard (build/, .dart_tool/, Pods,
gradle, etc.) en prévision du scaffolding Flutter (ticket #2), ainsi que
la configuration d'orchestration IdeA (agents, mémoire, tickets, sprints).
L'état d'exécution transitoire (conversations, run/, live-state) reste
ignoré du versionnement.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,95 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# Visual Studio Code related
+.vscode/
+*.code-workspace
+
+# Flutter/Dart/Pub related
+**/doc/api/
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.pub-cache/
+.pub/
+/build/
+**/build/
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release
+android/.gradle/
+android/local.properties
+android/**/gradle-wrapper.jar
+android/key.properties
+*.jks
+*.keystore
+
+# iOS/Xcode related
+ios/Pods/
+ios/.symlinks/
+ios/Flutter/Flutter.framework
+ios/Flutter/Flutter.podspec
+ios/Flutter/App.framework
+ios/Flutter/Generated.xcconfig
+ios/Flutter/ephemeral/
+ios/Flutter/app.flx
+ios/Flutter/app.zip
+ios/Flutter/flutter_assets/
+ios/Flutter/flutter_export_environment.sh
+ios/ServiceDefinitions.json
+ios/Runner/GeneratedPluginRegistrant.*
+**/xcuserdata/
+**/*.pbxuser
+**/*.mode1v3
+**/*.mode2v3
+**/*.perspectivev3
+*.moved-aside
+DerivedData/
+*.hmap
+*.ipa
+*.dSYM.zip
+*.dSYM
+
+# Generated files
+**/*.g.dart
+**/*.freezed.dart
+**/*.gr.dart
+
+# Coverage
+coverage/
+
+# Environment / secrets
+.env
+.env.*
+!.env.example
+
+# IdeA orchestration — état d'exécution transitoire (pas du code applicatif)
+.ideai/run/
+.ideai/conversations/
+.ideai/requests/
+.ideai/background-tasks/
+.ideai/live-state.json
+.ideai/layouts.json