refactor(core): using import defer

[chenjiahan]

Summary

WIP

TODO

• Rspack panic (@ahabhgk )

• Rslint needs to upgrade typescript-go to support import defer. (Port "Add support for import defer proposal"  microsoft/typescript-go#1826)
• Prettier does not support import defer yet (can be resolved via @prettier/plugin-oxc) (typescript import defer error prettier/prettier#18180)

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

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[Copilot]

Pull Request Overview

This PR refactors dynamic imports to use deferred imports, converting async module loading to synchronous top-level imports with the defer modifier. This optimization eliminates unnecessary async operations while enabling Rspack's experimental deferImport feature for better build performance.

Key changes:

• Convert dynamic import() calls to defer * as imports across multiple server-side modules
• Change async functions to synchronous where dynamic imports were the only async operations
• Enable Rspack's experimental deferImport feature in the build configuration
• Update TypeScript module configuration from ES2022 to esnext
• Add @prettier/plugin-oxc for enhanced code formatting

Reviewed Changes

Copilot reviewed 16 out of 17 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
scripts/config/tsconfig.json	Updated module target to esnext to support newer module features
packages/core/src/server/runner/asModule.ts	Replaced dynamic import with deferred import for node:vm
packages/core/src/server/prodServer.ts	Replaced dynamic imports with deferred imports for node:zlib and converted createHttpServer call to synchronous
packages/core/src/server/open.ts	Replaced dynamic imports with deferred imports for node:child_process and node:util, made getHostInUrl synchronous
packages/core/src/server/httpServer.ts	Replaced dynamic imports with deferred imports for http modules and converted function to synchronous
packages/core/src/server/hmrFallback.ts	Replaced dynamic import with deferred import for node:dns
packages/core/src/server/helper.ts	Replaced dynamic imports with deferred imports for node:net and made getHostInUrl synchronous
packages/core/src/server/devServer.ts	Removed await from createHttpServer call
packages/core/src/server/cliShortcuts.ts	Replaced dynamic import with deferred import for node:readline
packages/core/src/plugins/cache.ts	Removed await from hash function call
packages/core/src/loadConfig.ts	Replaced dynamic import with deferred import for jiti
packages/core/src/helpers/index.ts	Converted hash function from async to sync with deferred crypto import
packages/core/src/createContext.ts	Removed await from hash function call
packages/core/rslib.config.ts	Enabled Rspack's experimental deferImport feature
package.json	Added @prettier/plugin-oxc dev dependency
.prettierrc	Configured Prettier to use oxc plugin
pnpm-lock.yaml	Updated lock file with new dependencies

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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