Add MimeType utility functions

[Copilot]

This PR adds a comprehensive set of MIME type utility functions to the javascript-utils library.

Functions Added

• isImageMimeType(mimeType?: string): boolean - Check if MIME type is for images (image/*)
• isPdfMimeType(mimeType?: string): boolean - Check if MIME type is for PDF files (application/pdf)
• isVideoMimeType(mimeType?: string): boolean - Check if MIME type is for videos (video/*)
• isAudioMimeType(mimeType?: string): boolean - Check if MIME type is for audio (audio/*)
• isTextMimeType(mimeType?: string): boolean - Check if MIME type is for text (text/*)
• isApplicationMimeType(mimeType?: string): boolean - Check if MIME type is for applications (application/*)

Usage Examples

import { isImageMimeType, isPdfMimeType, isVideoMimeType } from '@neolution-ch/javascript-utils';

// Image types
isImageMimeType('image/jpeg'); // true
isImageMimeType('image/png'); // true
isImageMimeType('video/mp4'); // false

// PDF documents
isPdfMimeType('application/pdf'); // true
isPdfMimeType('image/jpeg'); // false

// Video files
isVideoMimeType('video/mp4'); // true
isVideoMimeType('video/webm'); // true
isVideoMimeType('audio/mp3'); // false

Key Features

• Robust input handling: Gracefully handles null/undefined inputs (returns false)
• Case-insensitive: MIME type checking works regardless of case
• Whitespace tolerant: Automatically trims whitespace from inputs
• Format validation: Ensures proper MIME type format (requires type/subtype pattern)
• Comprehensive testing: 100% test coverage with extensive edge cases

Implementation Details

• Created src/lib/mimeType.ts with all utility functions
• Created src/lib/mimeType.spec.ts with comprehensive test suite (102 test cases)
• Added export to src/index.ts to make functions available
• Follows existing library patterns for parameter validation and JSDoc documentation
• Maintains 100% test coverage requirement

Testing

All tests pass including:

• Input validation (null, undefined, non-strings)
• Valid MIME type detection for each category
• Case insensitivity verification
• Whitespace handling
• Invalid format rejection
• Cross-category validation (ensuring image functions reject video types, etc.)

Fixes #44.

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npm i https://pkg.pr.new/neolution-ch/javascript-utils/@neolution-ch/javascript-utils@69

commit: f4f85fe

[neotrow]

@copilot the check-changelog is failing because you didn't add you changes to the CHANGELOG.md.

Please add it under the unreleased section, make sure prettier is happy after adding it.

[Copilot]

@copilot the check-changelog is failing because you didn't add you changes to the CHANGELOG.md.

Please add it under the unreleased section, make sure prettier is happy after adding it.

Added the MIME type utility functions to the CHANGELOG.md under the unreleased section. Prettier formatting verified and all tests pass with 100% coverage. (commit ca9fe58)

[github-actions]

Package	Line Rate	Branch Rate	Complexity	Health
main	100%	100%	0	✔
Summary	100% (145 / 145)	100% (73 / 73)	0	✔