fix: use path extensions for esm

[maheshsundaram]

Description

Note: If this change is against the project's maintainers' goals, feel free to close. I forked this library and made this change so that I could utilize this library in browser code using ES modules and importmap.

ES Module resolution does not perform automatic file extension resolution and tsc does not rewrite import statements during emit. The recommendation from the Typescript handbook is to use the extension of the output files.

Add .js file extensions to imports

Motivation and Context

Provide valid ES module

Types of changes

• [ ] 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 change)
• [x] Enhancement (changes that improvement of current feature or performance)
• [x] Refactoring (changes that neither fixes a bug nor adds a feature)
• [ ] Test Case (changes that add missing tests or correct existing tests)
• [X] Code style optimization (changes that do not affect the meaning of the code)
• [ ] Docs (changes that only update documentation)
• [ ] Chore (changes that don't modify src or test files)

Self Check before Merge

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.

[vivcat[bot]]

👋 @maheshsundaram

💖 Thanks for opening this pull request! 💖

Please follow the contributing guidelines. And we use semantic commit messages to streamline the release process.

Examples of commit messages with semantic prefixes:

• fix: don't overwrite prevent_default if default wasn't prevented
• feat: add graph.scale() method
• docs: graph.getShortestPath is now available

Things that will help get your PR across the finish line:

• Follow the TypeScript coding style.
• Run npm run lint locally to catch formatting errors earlier.
• Document any user-facing changes you've made.
• Include tests when adding/changing behavior.
• Include screenshots and animated GIFs whenever possible.

We get a lot of pull requests on this repo, so please be patient and we will get back to you as soon as we can.

[codecov[bot]]

Codecov Report

Patch coverage: 100.00% and no project coverage change

Comparison is base (b751cbf) 62.93% compared to head (7acfc92) 62.93%.

Additional details and impacted files

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