fix: Accept partial plugin options

[danreeves]

Resolves #9

Currently the PluginOptions exported by babel-plugin-react-compiler expects most keys to be populated but in reality the babel plugin accepts partial objects, so it would be better if defineReactCompilerLoaderOption accepted Partial<PluginOptions>.

defineReactCompilerLoaderOption({ target: '17' }) is valid but the types won't accept it.

As a workaround, users can just set options: { target: '17' }, but then you lose typing.

[SukkaW]

Ideally, we really should be aligned with the upstream types.

Let's say, if the React Compiler has updated options, that if you have A configured, you must also specify B, or you should not specify them at all:

XOR<{}, { A: unknown, B: unknown }>

Now with partial we can't do type safe anymore.

[SukkaW]

Maybe the PR should be opened to the upstream instead. IIRC they are using zod, so this should be very easy to update.