Add option to disable ES transforms in sucrase

[Mrtenz]

tsup uses sucrase to transpile ESM to CJS when code splitting is enabled:

tsup/src/plugins/cjs-splitting.ts

Lines 21 to 31 in 83c7c7f

	const { transform } = await import('sucrase')
	const result = transform(code, {
	filePath: info.path,
	transforms: ['imports'],
	sourceMapOptions: this.options.sourcemap
	? {
	compiledFilename: info.path,
	}
	: undefined,
	})

Unfortunately there is no way right now to specify the settings for sucrase. In our case, we wanted to disable the optional chaining polyfill that sucrase adds, since it's problematic for static analysis. The only way to do so seems to be by setting disableESTransforms: true in the options. It would be great if tsup had an option to set this.

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[FrederikBolding]

To be clear, @Mrtenz and I are willing to submit a PR for this feature. But we would need some guidance on how best to implement it. E.g. should we simply add a configuration option for this or automatically determine the value of disableESTransforms by looking at the target?