feat: Add text processing features

[owdax]

Description

This PR adds comprehensive text processing features to SwiftDevKit, including string transformations, metrics calculations, and text extraction utilities. These features provide developers with powerful tools for common string manipulation tasks, string similarity comparisons, and pattern extraction.

Fixes #N/A (no linked issue)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist:

• My code follows the style guidelines of SwiftDevKit
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[codecov-commenter]

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Codecov Report

Attention: Patch coverage is 75.08711% with 143 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...es/SwiftDevKit/TextProcessing/String+Metrics.swift	0.00%	133 Missing ⚠️
...iftDevKit/TextProcessing/StringTransformable.swift	0.00%	8 Missing ⚠️
.../SwiftDevKit/TextProcessing/String+Transform.swift	98.11%	2 Missing ⚠️

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Files with missing lines	Coverage Δ
...SwiftDevKit/TextProcessing/String+Extraction.swift	100.00% <100.00%> (ø)
...itTests/TextProcessing/StringExtractionTests.swift	100.00% <100.00%> (ø)
...KitTests/TextProcessing/StringTransformTests.swift	100.00% <100.00%> (ø)
.../SwiftDevKit/TextProcessing/String+Transform.swift	98.11% <98.11%> (ø)
...iftDevKit/TextProcessing/StringTransformable.swift	0.00% <0.00%> (ø)
...es/SwiftDevKit/TextProcessing/String+Metrics.swift	0.00% <0.00%> (ø)