- Add coverlet.collector package for code coverage collection
- Remove unused conditional package references for netstandard2.0 and net46
- Clean up project file by removing obsolete framework-specific dependencies
- Ensure consistent test tooling across the project

- Add TestCryptoHelpers with DummyKeyEncryptionKey for test isolation
- Create factory methods for encryption algorithms and settings
- Enable end-to-end encryption testing without external key providers
- Centralize test crypto setup to reduce code duplication across tests
- Add empty UnsafeAccessors.Net8.cs placeholder for future .NET 8 support

- Add tests for patch operation validation on encrypted paths
- Verify Increment operations are blocked on encrypted properties
- Test that non-encrypted paths allow patch operations to pass through
- Ensure proper error messaging when increment operations are attempted on encrypted fields
- Cover both positive and negative test scenarios for patch operation encryption

- Test diagnostics data collection during encrypt/decrypt operations
- Verify properties encrypted/decrypted counts are captured correctly
- Ensure start time and duration are recorded in diagnostics context
- Test diagnostics behavior with null properties and edge cases
- Cover both encrypt and decrypt diagnostic data collection scenarios

- Add comprehensive round-trip encryption/decryption tests
- Test primitive types (string, int, bool, double), arrays, and nested objects
- Verify proper handling of large Unicode strings and special characters
- Test ID field escaping for URL-safe Base64 encoding
- Add tests for DateTime/DateTimeOffset rejection with proper error messages
- Test feed response decryption and aggregation scenarios
- Cover cancellation token handling (current pass-through behavior)
- Test invalid Base64 handling and error propagation

- Test null argument validation for EncryptAsync and DecryptAsync
- Verify proper error handling when encryption settings are missing
- Test behavior when properties are configured but mappings are missing
- Ensure proper ArgumentException messages for invalid configurations
- Test stream disposal behavior on validation failures
- Cover edge cases in settings validation and error propagation

- Add comprehensive TypeMarker serialization round-trip tests
- Test boolean, long, double, and string serialization/deserialization
- Verify proper handling of special double values (NaN, Infinity)
- Test very large string serialization (1 MiB) for performance validation
- Add tests for decimal to double coercion with precision loss
- Test unsupported type rejection (Guid, byte[], TimeSpan, Uri)
- Verify proper error messages for invalid type operations
- Add overflow handling tests for numeric type edge cases

- Test Base64 URI-safe encoding for ID fields with problematic characters
- Verify proper escaping of '/', '+', '?', '#', '\' characters in IDs
- Test round-trip encoding/decoding without data loss
- Add Unicode string testing with emojis and multi-byte characters
- Test large mixed-Unicode ID strings for performance validation
- Ensure no whitespace padding in encoded results
- Verify proper handling of URL-unsafe characters in encrypted IDs

- Test encryption/decryption with deeply nested JSON structures
- Verify handling of documents approaching MaxDepth limit (64 levels)
- Test JSON traversal with complex nested objects and arrays
- Add tests for null-only leaf traversal without crypto operations
- Verify proper structural preservation during deep traversal
- Test escaping behavior in nested document structures
- Ensure performance with large nested documents

- Test proper stream disposal behavior in encrypt/decrypt operations
- Verify new stream instances are returned from operations
- Test seekable stream requirements for decrypt operations
- Add tests for null input stream handling
- Test no-op decryption scenarios with empty property configurations
- Verify zero counts returned when no properties are configured for decryption
- Test scenarios where properties are configured but not present in documents

- Test DeserializeAndDecryptResponseAsync with various feed shapes
- Verify proper handling of empty Documents arrays
- Test mixed document types in feed responses (objects, primitives)
- Add validation for required 'Documents' property in feed responses
- Test error handling for malformed feed response structures
- Verify diagnostics aggregation across multiple documents in feeds
- Test deeply nested documents within feed responses
- Ensure proper feed contract validation and error messaging

- Add randomized encryption algorithm tests verifying different ciphertexts
- Test that randomized encryption produces different ciphers for same input
- Verify both ciphertexts decrypt back to original data correctly
- Add diagnostics edge case tests for missing/null properties
- Test diagnostic counting with various property configurations
- Add placeholder tests for null crypto path validation (requires test seam)
- Cover diagnostic behavior when properties are configured but missing from documents

- Update Visual Studio solution file to newer version (17.14.36301.6)
- Add VS Code tasks.json with dotnet build tasks for development workflow
- Configure build tasks with proper error formatting and console logging
- Support multiple build task entries for different project contexts
- Enable better development experience with IDE integration

- Add placeholder UnsafeAccessors.Net8.cs file for future .NET 8 features
- Maintain directory structure for upcoming .NET 8 specific implementations
- Prepare infrastructure for potential unsafe accessor patterns in .NET 8

…l classes

- Consolidated 19+ fragmented test classes into 5 logical groupings
- Replaced arbitrary test splitting with functionality-based organization
- Created single EncryptionProcessorTests partial class structure:
  • CoreFunctionality.cs - End-to-end encryption/decryption, stream handling, JSON traversal
  • Validation.cs - Argument validation, settings validation, unsupported types
  • EdgeCases.cs - Depth handling, overflow scenarios, no-op operations, diagnostics
  • DataFormatEncoding.cs - ID escaping, Unicode handling, feed responses, value streams
  • Cryptography.cs - Randomized algorithms, encryption modes, key management

Benefits:
- Reduced test file fragmentation (19+ files → 6 files)
- Improved maintainability with shared utilities
- Better logical organization by functionality
- Preserved all existing test functionality
- Enhanced developer experience with meaningful test groupings

…tream handling

- Consolidated fragmented test classes into organized partial classes
- Added StreamTestHelpers utility class with TrackingStream for better stream disposal testing
- Improved stream handling tests with proper disposal verification
- Fixed BigInteger overflow test to not expect exceptions
- Updated diagnostics tests to reflect current implementation behavior
- Removed deprecated null crypto path tests and local KEK implementations
- Enhanced test maintainability by reducing class fragmentation from 19+ to 5 logical groupings

- Remove Visual Studio version changes (17 -> 16)
- Remove build configurations for unrelated project
- Keep solution file consistent with upstream

…erhaul