fix(types): use TS interfaces only for public api

[dai-shi]

following pmndrs/zustand#1106

It turns out, we don't have public interface 😓 .

This sort of reverts/revisits #474 and #493.

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Size Change: 0 B

Total Size: 48.3 kB

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Filename	Size
dist/esm/index.js	712 B
dist/esm/macro.js	613 B
dist/esm/macro/vite.js	697 B
dist/esm/utils.js	3.94 kB
dist/esm/vanilla.js	1.9 kB
dist/index.js	880 B
dist/macro.js	910 B
dist/macro/vite.js	982 B
dist/system/index.development.js	871 B
dist/system/index.production.js	508 B
dist/system/macro.development.js	721 B
dist/system/macro.production.js	555 B
dist/system/macro/vite.development.js	828 B
dist/system/macro/vite.production.js	653 B
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dist/system/utils.production.js	2.83 kB
dist/system/vanilla.development.js	2 kB
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dist/umd/index.production.js	670 B
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dist/umd/macro/vite.production.js	874 B
dist/umd/utils.development.js	4.73 kB
dist/umd/utils.production.js	3.02 kB
dist/umd/vanilla.development.js	2.11 kB
dist/umd/vanilla.production.js	1.32 kB
dist/utils.js	4.58 kB
dist/vanilla.js	2.01 kB

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