use node export condition when bundling

[Rich-Harris]

closes #9264. The issue was that the dependency in question, vidstack, has a bunch of different exports for different conditions; the node condition points at a module that is capable of running on the server.

When running in dev and preview, the module was loaded through Node, and so naturally the node condition was used. But adapter-node bundles the dependency using the default condition, which points at a production browser build.

This PR fixes it by using the node export condition for resolution when bundling dependencies.

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