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What's changed and what's your intention?

Currently in our batch StorageTable and streaming StateTable, we shared a similar logic to compute vnode.

if vnode_bitmap.is_none() {
    DEFAULT_VNODE
} else if vnode_col_index.is_some() {
    // get vnode directly from row
} else {
    assert!(dist_key_in_pk_indices is not empty);
    // compute vnode by provided dist key indices
}

Code with similar logic appear in both StorageTable and StateTable. In this PR, we unify this logic to the risingwave_storage::table::Distribution. The type is renamed to TableDistribution to be distinguished with the optimizer Distribution. The TableDistribution will hold a enum with the following definition

enum ComputeVnode {
    Singleton,
    DistKeyIndices {
        /// Indices of distribution key for computing vnode, based on the all columns of the table.
        dist_key_in_pk_indices: Vec<usize>,
    },
    VnodeColumnIndex {
        /// Indices of vnode columns.
        vnode_col_idx_in_pk: usize,
    },
}

Checklist

• I have written necessary rustdoc comments
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