Minified import for all locales

I'm currently using all locales and they take up about half of my app's file size (very small app). I was wondering if there would be a way to build the locales in dayjs (https://github.com/iamkun/dayjs/tree/dev/src/locale) so that the redundancies are not repeated over each import, without breaking anything.

Start by reviewing the locale modules under src/locale and how importing all locales is currently built. Define a build or packaging approach that removes repeated locale content while preserving existing locale behavior, then verify that all locales still work and the resulting application bundle is smaller.

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