docs(www): add resizable control example

[Need-an-AwP]

add a new resizable panel example
it shows a way to control the panel from external
the code is the same in both default and NewYork

i used pnpm build:registry to let the script write necessary registry code, so that i can run pnpm dev to see the result in dev env
but there are too many file changes, so this commit only includes essential changes directly related to the example

[vercel]

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