feat: add symbol/to-string-tag package

[kaushal-kumar-it]

Resolves #8482

Description

What is the purpose of this pull request?

This pull request implements the RFC proposing the addition of the symbol/to-string-tag package.

The package is modeled after existing symbol utilities in the repository, including:

• symbol/has-instance
• symbol/iterator
• symbol/async-iterator
• symbol/is-concat-spreadable

The new package exports Symbol.toStringTag when available in the current environment.

Additional implementation details include:

• copying one of the existing symbol packages as a template
• renaming the package directory and files accordingly
• replacing identifiers throughout the package
  (e.g., has-instance → to-string-tag, HasInstanceSymbol → ToStringTagSymbol)
• ensuring the copyright year is 2025
• updating descriptions based on MDN documentation for Symbol.toStringTag
• updating examples to reflect the symbol's intended usage
• running tests, benchmarks, and examples to verify correctness
• checking for any copy-paste errors

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• None.

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines.

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Documentation (including examples)
• [] Research and understanding
• Code generation
• Test/benchmark generation

Disclosure

This PR includes descriptive text drafted with the assistance of ChatGPT to ensure that the RFC details and PR documentation are clear and complete. All code changes were written and validated manually.

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Coverage Report

Package	Statements	Branches	Functions	Lines
symbol/to-string-tag	$\color{green}103/103$ $color{green}+100.00%$	$\color{red}2/3$ $color{green}+66.67%$	$\color{green}0/0$ $color{green}+100.00%$	$\color{green}103/103$ $color{green}+100.00%$

The above coverage report was generated for the changes in this PR.