feat(compiler): add oxc builder

[GNURub]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

Nest CLI currently supports tsc, swc, and webpack as builder options.

There is no OXC-based builder available, so users cannot compile projects through
oxc-transform using nest build or nest start.

Issue Number: N/A

What is the new behavior?

This PR adds an experimental oxc builder powered by oxc-transform.

The new builder supports:

• nest build --builder oxc
• nest start --builder oxc
• Type checking through the existing TypeScript type checker flow
• Watch mode
• Source maps and inline source maps
• Declaration files and declaration maps
• .ts, .tsx, .mts, and .cts compilation
• Proper output extensions for .mts -> .mjs and .cts -> .cjs
• Cleanup of generated outputs when source files are deleted in watch mode

It also adds builder validation support for oxc in the build and start commands,
plus unit test coverage for the new compiler behavior and command integration.

The implementation uses oxc-transform@0.89.0 conservatively to avoid raising the
current Node.js engine requirement.

Does this PR introduce a breaking change?

• Yes
• No

This is additive. Existing builders and configuration continue to work as before.

Other information

Validation performed:

• npm run build
• npm test -- --runInBand --no-watchman
• npx tsc --noEmit
• git diff --check

[id6tm-mteterel]

Using the default NestJS template, I have the following error on build with oxc :

OXC Running...

 Error  
  x `await` is only allowed within async functions and at the top levels of
  | modules
   ,-[src/main.ts:8:1]
 7 | }
 8 | await bootstrap();
   : ^^^^^
   `----

The same code works with tsc, swc and rspack (on v12).

Compiling with oxc creates a runtime dependency on @oxc-project/runtime for the decorators support.

It would be a nice addition to have a log during watch mode reload, similar to how it was implemented on the rspack version in https://github.com/nestjs/nest-cli/blob/v12.0.0/lib/compiler/rspack-compiler.ts#L134