fix(storage): standardize URL construction to use v1 API paths

[thiyaguk09]

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> 🦕

[gemini-code-assist]

Code Review

This pull request updates the library to use versioned API paths (/storage/v1) across all storage resources and standardizes the use of JSON content-type headers. It also refactors the File.isPublic method and the Iam class. Review feedback identifies a regression in the isPublic refactor where interceptors are no longer applied, a potential URL construction issue regarding the apiEndpoint protocol, and a recommendation to replace 'any' types with specific interfaces for better type safety.