feat: how to disable inline dts

[litingyes]

What problem does this feature solve?

refer: qmhc/unplugin-dts#439

unplugin-dts use volar to build dts and seems that it is not possible to turn off inline dts

This can cause problems when packaging component libraries; the type declaration files are too large.

What does the proposed solution look like?

N/A

[KazariEX]

Please track vuejs/core#12935.