Build watch mode remaining issues

[sapphi-red]

• does not work on Windows due to [Bug]: calling this.addWatchFile with / separated paths on Windows does re-transform the modules rolldown/rolldown#4385
• closeBundle hook is not called for watch mode ([Feature Request]: event.result.close() support for BUNDLE_END event rolldown/rolldown#4380)
• watcher.off is not implemented yet ([Feature Request]: watcher.off method to remove event listener rolldown/rolldown#4382) but needed for tests (

  rolldown-vite/playground/vitestSetup.ts

  Lines 295 to 309 in b040d54

  	export async function notifyRebuildComplete(
  	watcher: RollupWatcher,
  	): Promise<RollupWatcher> {
  	let resolveFn: undefined | (() => void)
  	const callback = (event: RollupWatcherEvent): void => {
  	if (event.code === 'END') {
  	resolveFn?.()
  	}
  	}
  	watcher.on('event', callback)
  	await new Promise<void>((resolve) => {
  	resolveFn = resolve
  	})
  	return watcher.off('event', callback)
  	}

  )
• [Feature Request]: shouldTransformCachedModule hook support rolldown/rolldown#4389

refs #67