fix: prevent V8 tool scripts from being loaded as builtin modules

[abdulfarid-dev]

This patch prevents Node.js from attempting to load V8 tool scripts under
internal/deps/v8/tools/ as builtin modules.

These files are part of V8’s internal tooling and are not valid Node.js
builtins. When required or imported with --expose-internals, the loader
attempts to treat them as builtin CJS modules, which results in either:

• SyntaxError: Unexpected token 'export'
  (because the V8 tool scripts contain ESM syntax), or
• AssertionError in BuiltinLoader::LookupAndCompileFunction
  (data->IsValue()), aborting the process.

This change adds a guard in loadBuiltinModule() to skip any module whose
path starts with internal/deps/v8/tools/, and also adds a defensive check
to avoid calling compileForPublicLoader() when no builtin module entry
exists.

This aligns the behavior with expectations and avoids a crash when users
attempt to load these paths with --expose-internals.

Fixes: #60865

[nodejs-github-bot]

Review requested:

• @nodejs/loaders

[aduh95]

I don't think that's the right place to pass that, we don't want to impact the happy path. Also, it makes no sense to add those to the list of builtin modules in src/node_builtins.cc only to filter them out on the JS side.