Add DICOM runtime key parameters

[Copilot]

This PR implements the ability to specify key values as optional parameters when de-identifying a specific data set in AnonymizerEngine.AnonymizeDataset, allowing runtime override of configuration-based keys.

Changes Made

New RuntimeKeySettings Class: Added a new class to hold optional runtime key values for cryptoHashKey, dateShiftKey, and encryptKey that can override configuration defaults.

Enhanced AnonymizerEngine: Added a new overload AnonymizeDataset(DicomDataset dataset, RuntimeKeySettings runtimeKeySettings) while maintaining full backward compatibility with the existing AnonymizeDataset(DicomDataset dataset) method.

Updated Processors: Modified CryptoHashProcessor, DateShiftProcessor, and EncryptProcessor to use runtime keys when available, falling back to configuration keys when not provided.

ProcessContext Enhancement: Extended ProcessContext to pass runtime keys to processors through the anonymization pipeline.

Usage Example

var engine = new AnonymizerEngine("configuration.json");

// Existing behavior - uses configuration keys
engine.AnonymizeDataset(dataset);

// New functionality - uses runtime keys
var runtimeKeys = new RuntimeKeySettings 
{ 
    CryptoHashKey = "runtime-crypto-key",
    DateShiftKey = "runtime-date-key",
    EncryptKey = "runtime-encrypt-key-12345678901234567890123456"
};
engine.AnonymizeDataset(dataset, runtimeKeys);

Benefits

• Per-dataset anonymization: Different datasets can use different keys while sharing the same configuration
• Dynamic key generation: Keys can be generated programmatically based on external factors
• Enhanced security: Keys can be managed separately from configuration files
• Zero breaking changes: All existing functionality is preserved

Testing

Added comprehensive unit tests covering:

• Different runtime keys producing different results
• Same runtime keys producing consistent results
• Fallback to configuration keys when no runtime key provided
• DateShift processor with runtime keys

All existing tests continue to pass, demonstrating no regressions were introduced.

Fixes #249.

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[jovinson-ms]

@copilot can you change all references to "seed" to "key" to match the terminology in the existing code? And also move the documentation from a separate file to be a section in the main dicom documentation md file.

[Copilot]

@copilot can you change all references to "seed" to "key" to match the terminology in the existing code? And also move the documentation from a separate file to be a section in the main dicom document...

I've updated all references from "seed" to "key" to match the existing codebase terminology and moved the documentation from the separate file to the main DICOM documentation file as requested. Changes include:

Terminology Updates:

• Renamed RuntimeSeedSettings to RuntimeKeySettings
• Updated all method parameters, properties, and comments to use "key" instead of "seed"
• Updated test class and method names accordingly

Documentation Consolidation:

• Moved content from DICOM/RuntimeSeedExample.md to docs/DICOM-anonymization.md as a new "Runtime Key Parameters" section
• Updated all documentation examples to use "key" terminology
• Removed the separate documentation file

All tests pass and the code now uses consistent terminology with the rest of the codebase.

Commit: 3a5c1d7