Feat: Add deno support in create-next-app and add docs

[brrock]

• Feat: Add Deno support in create-next-app
• Chore: Lint
• Add docs in the testing section to install needed packages for testing

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For Contributors

Improving Documentation

• Run pnpm prettier-fix to fix formatting issues before opening the PR.
• Read the Docs Contribution Guide to ensure your contribution follows the docs guidelines.

Adding or Updating Examples

• Follow the examples guidelines from our contributing doc.
• Make sure the linting passes by running pnpm build && pnpm lint. See linting guidelines.

Fixing a Bug

• Related issues linked using fixes #number.
• Tests added. See: writing tests for Next.js.
• Errors have a helpful link attached, see contributing guidelines.

Adding a Feature

• Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR. (A discussion must be opened, see discussion thread).
• Related issues/discussions are linked using fixes #number.
• End-to-end tests added: e2e tests.
• Documentation added.
• Telemetry added to determine feature usage.
• Errors have a helpful link attached, see contributing guidelines.

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For Maintainers

• Minimal description (aim for explaining to someone not on the team to understand the PR).
• When linking to a Slack thread, consider sharing details of the conclusion.
• Link both the Linear (Fixes NEXT-xxx) and the GitHub issues.
• Add review comments if necessary to explain the logic behind a change.

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What?

This PR adds support for using Deno in create-next-app, allowing the user to use Deno as a package manager with the same flag that works for pnpm or yarn. It also detects if the script is run using Deno.

Why?

Deno is gaining fast adoption with its new 2.0 update. It’s much faster than npm and has many additional features.

How?

• In get-pkg-manager.ts, the code checks if the Deno type exists, which will only happen if you run the script using Deno.
• In install.ts, it checks if the package manager is Deno based on the last file.
• In index.ts, it implements the --use-deno flag to indicate that Deno is being used as the package manager.

[brrock]

why did Job unable able to validate for brrock on PR #71396 fail what does that mean

[brrock]

@ijjk

[brrock]

@ijjk

[brrock]

Can I see some activity any news guys

[samcx]

@brrock Taking a look!

[delbaoliveira]

Thank you for the docs updates @brrock, could you please resolve the merge conflicts? 🙏🏼

[brrock]

Yep

[brrock]

Sorry for slow response

[brrock]

All ready to go

[brrock]

@samcx ready to review

[brrock]

Ready

[brrock]

@leerob

[samcx]

@brrock Looks like there are still merge conflicts!

[brrock]

Sorting out when I get home

[brrock]

About to remake