Copy docstring from the Table's sync method to the extracted sync method

clients/typescript/src/client/model/client.ts

@@ -112,6 +112,21 @@ export class ElectricClient<
   DB extends DbSchema<any>
 > extends ElectricNamespace {
   public sync: Omit<IShapeManager, 'subscribe'> & {
+    /**
+     * Subscribes to the given shape, returnig a {@link ShapeSubscription} object which
+     * can be used to wait for the shape to sync initial data.
+     *
+     * NOTE: If you establish a shape subscription that has already synced its initial data,
+     * awaiting `shape.synced` will always resolve immediately as shape subscriptions are persisted.
+     * i.e.: imagine that you re-sync the same shape during subsequent application loads.
+     * Awaiting `shape.synced` a second time will only ensure that the initial
+     * shape load is complete. It does not ensure that the replication stream
+     * has caught up to the central DB's more recent state.
+     *
+     * @param i - The shape to subscribe to
+     * @param key - An optional unique key that identifies the subscription
+     * @returns A shape subscription
+     */
     subscribe: (
       i: ShapeInputWithTable,
       key?: string