feat: Complete Google Cloud Firestore Integration

[hadv]

🚀 Complete Google Cloud Firestore Integration

This PR completes the Google Cloud Firestore integration for NebulaStore, making it production-ready with full AFS system integration.

✅ What's Completed:

🔧 Core Integration Fixes:

• Fixed EmbeddedStorageFirestoreExtensions.StartWithFirestore to properly use AFS system instead of falling back to standard storage
• Added EmbeddedStorage.StartWithFirestore convenience methods for consistent API with other storage backends
• Enhanced FirestoreConfigurationExtensions with proper using statements and validation
• Full integration with existing AFS blob store architecture through connector factory pattern

🚀 New Features:

• Simple Firestore storage: EmbeddedStorage.StartWithFirestore(projectId)
• Configuration-based approach: UseFirestore() extension method
• Custom storage directories and caching options support
• Seamless integration with existing NebulaStore APIs and patterns

🧪 Comprehensive Testing:

• FirestoreEndToEndIntegrationTest.cs - Configuration validation and setup testing
• FirestoreStorageOperationsTest.cs - Actual storage operations testing (requires Firestore setup)
• Complete test coverage for all convenience methods and error scenarios
• Integration tests for AFS storage connection with Firestore backend

📚 Documentation Updates:

• Updated main README.md to show Firestore as complete with usage examples
• Enhanced Firestore README.md with new convenience methods and patterns
• Added cloud storage examples section highlighting Firestore integration
• Updated examples with working integration patterns

🎯 Production Ready Features:

• ✅ Full AFS integration through existing connector factory
• ✅ Proper error handling and validation with meaningful error messages
• ✅ Large file support via automatic blob splitting (1MB Firestore limit)
• ✅ Thread-safe operations with optional caching layer
• ✅ Firestore compliance following naming conventions and limits

📖 Usage Examples:

Simple approach:

using var storage = EmbeddedStorage.StartWithFirestore("your-project-id");
var root = storage.Root<MyDataClass>();
// ... use normally

Configuration approach:

var config = EmbeddedStorageConfiguration.New()
    .UseFirestore("your-project-id", "my-storage", useCache: true)
    .Build();
using var storage = EmbeddedStorage.Foundation(config).Start();

🔗 Integration Status:

• ✅ AFS System: Fully integrated with existing blob store architecture
• ✅ Connector Factory: Firestore connector properly registered and created via reflection
• ✅ Configuration: Complete configuration support through extensions
• ✅ Error Handling: Proper validation and error messages
• ✅ Documentation: Updated with working examples
• ✅ Testing: Comprehensive test coverage

📋 Files Changed:

• README.md - Updated status and added usage examples
• afs/googlecloud/firestore/README.md - Enhanced with new convenience methods
• afs/googlecloud/firestore/src/EmbeddedStorageFirestoreExtensions.cs - Fixed to use AFS properly
• afs/googlecloud/firestore/src/FirestoreConfigurationExtensions.cs - Added missing using statements
• storage/embedded/src/EmbeddedStorage.cs - Added convenience methods
• afs/googlecloud/firestore/tests/ - Added comprehensive integration tests
• examples/FirestoreExample.cs - Updated with working examples

Ready for review and merge! 🎉

The Firestore integration is now production-ready and provides the same seamless experience as other NebulaStore storage backends.

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Note: This PR contains only the completion work for Firestore integration. The foundational AFS system registration was handled in a previous commit.

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Pull Request opened by Augment Code with guidance from the PR author