Refactor(js-ciphers): export Vigenère as ESM module + package.json + example

[immortal71]

Refactors the existing JavaScript Vigenère implementation into a reusable Node ESM package under js-ciphers/

[Copilot]

Pull Request Overview

This PR refactors the JavaScript Vigenère cipher implementation into a reusable ESM module by separating the test code from the module itself, adding proper Node.js package configuration, and providing standalone example usage.

Key changes:

• Removed inline test code from vigenere.js to keep it as a pure exportable module
• Created test.js with example usage demonstrating encryption/decryption
• Added package.json with ESM configuration to enable proper Node module support

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 7 comments.

File	Description
js-ciphers/vigenere.js	Removed inline test code and added explanatory comments about ESM exports
js-ciphers/test.js	New file with example usage demonstrating the Vigenère cipher
js-ciphers/package.json	New package configuration enabling ESM module support
README.md	Formatting changes including emoji removal and indentation adjustments

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[Copilot]

The keyword 'vigenere' should be spelled 'vigenère' (with accent) for consistency and correctness.

Suggested change

	"description": "Collection of small JavaScript cipher utilities (Vigenere)",
	"main": "vigenere.js",
	"type": "module",
	"keywords": ["cipher", "vigenere", "cryptography", "ciphers"],
	"description": "Collection of small JavaScript cipher utilities (Vigenère)",
	"main": "vigenere.js",
	"type": "module",
	"keywords": ["cipher", "vigenère", "cryptography", "ciphers"],

[Copilot]

The entire header section (title through 'What's Inside?') is duplicated on lines 30-52. Additionally, the code block starting at line 25 is incomplete and cuts off at line 29, followed by the duplicate content. Remove the duplicate lines 30-52 and complete the directory tree structure properly.

[Copilot]

Incorrect heading level. This should be ### (level 3) to match the preceding 'CLI Mode - File Encryption' section structure, not ## (level 2).

Suggested change

	## CLI Mode - File Decryption
	#### CLI Mode - File Decryption

[Copilot]

The Contributing, License, and Show Your Support sections are duplicated. These lines duplicate content already present on lines 187-201. Remove this duplicate content.

Suggested change

	## License
	This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.
	---
	## Show Your Support
	Give us a star if you found this helpful!