Replace direct comparisons with TargetMatcher and SourceMatcher

[konard]

Summary

This PR addresses issue #153 by replacing direct GetTarget and GetSource comparisons with the appropriate criterion matchers (TargetMatcher and SourceMatcher).

Changes Made

✅ Created SourceMatcher class

• Added SourceMatcher<TLinkAddress> following the same pattern as TargetMatcher
• Implements ICriterionMatcher<TLinkAddress> interface
• Provides efficient source matching functionality

✅ Updated ILinksExtensions methods

• Modified CountUsages method to use SourceMatcher and TargetMatcher instead of direct comparisons
• Updated Equals method to use criterion matchers for source and target validation
• Added proper using statement for Platform.Data.Doublets.CriterionMatchers

✅ Comprehensive test coverage

• Added CriterionMatchersTests with full test suite
• Tests for both TargetMatcher and SourceMatcher functionality
• Integration tests for updated CountUsages and Equals methods
• All tests pass successfully

Test Results

Test Run Successful.
Total tests: 25 (including 4 new tests)
     Passed: 24
     Skipped: 1

Technical Details

• The solution maintains backward compatibility while improving code organization
• Uses the established criterion matcher pattern for consistency
• Follows existing code conventions and documentation style
• No breaking changes to public APIs

Resolves

Fixes #153

🤖 Generated with Claude Code

Co-Authored-By: Claude noreply@anthropic.com