docs(editor): improve documentation for store class (#10949)

blocksuite/docs/api/@blocksuite/store/interfaces/StoreSlots.md

@@ -0,0 +1,60 @@
+[**@blocksuite/store**](../../../@blocksuite/store/README.md)
+
+***
+
+[BlockSuite API Documentation](../../../README.md) / [@blocksuite/store](../README.md) / StoreSlots
+
+# Interface: StoreSlots
+
+Slots for receiving events from the store.
+All events are rxjs Subjects, you can subscribe to them like this:
+
+```ts
+store.slots.ready.subscribe(() => {
+  console.log('store is ready');
+});
+```
+
+You can also use rxjs operators to handle the events.
+
+## Properties
+
+### blockUpdated
+
+> **blockUpdated**: `Subject`\<`StoreBlockUpdatedPayloads`\>
+
+***
+
+### historyUpdated
+
+> **historyUpdated**: `Subject`\<`void`\>
+
+This fires when the doc history is updated.
+
+***
+
+### ready
+
+> **ready**: `Subject`\<`void`\>
+
+This fires after `doc.load` is called.
+The Y.Doc is fully loaded and ready to use.
+
+***
+
+### rootAdded
+
+> **rootAdded**: `Subject`\<`string`\>
+
+This fires when the root block is added via API call or has just been initialized from existing ydoc.
+useful for internal block UI components to start subscribing following up events.
+Note that at this moment, the whole block tree may not be fully initialized yet.
+
+***
+
+### rootDeleted
+
+> **rootDeleted**: `Subject`\<`string`\>
+
+This fires when the root block is deleted via API call or has just been removed from existing ydoc.
+In most cases, you don't need to subscribe to this event.