fix(base): show skeleton while inline embed is being created, anchor at slash position

The Database slash command deleted the trigger text and then awaited
the create-base API before inserting the embed. During the wait the
editor sat empty (no visible state), and by the time the embed was
inserted the editor's selection had often drifted — so the new node
landed in the wrong place and the page appeared to "jump up" when the
response arrived.

Insert a placeholder baseEmbed node synchronously at the slash position
with pageId: null and a unique pendingKey. BaseEmbedView renders
BaseTableSkeleton while pendingKey is set — same skeleton BaseTable
shows on its own initial load, so the swap to the real table is a
visual no-op. Once the API responds, look up the placeholder by its
pendingKey and patch in the real pageId via setNodeMarkup. On API
failure, remove the placeholder and surface a toast. The pendingKey
attribute is non-serializing (parseHTML returns null, renderHTML
returns {}) so a placeholder can't survive a page reload as orphan.

apps/client/src/features/editor/components/base-embed/base-embed-view.tsx

@@ -2,6 +2,7 @@ import { NodeViewWrapper, NodeViewProps } from "@tiptap/react";
 import { Box, Text } from "@mantine/core";
 import { useEffect, useRef } from "react";
 import { BaseTable } from "@/features/base/components/base-table";
+import { BaseTableSkeleton } from "@/features/base/components/base-table-skeleton";
 import { useBaseQuery } from "@/features/base/queries/base-query";
 
 const SIDE_GUTTER = 8;
@@ -42,8 +43,12 @@ function applyExtension(wrapper: HTMLDivElement) {
 
 export function BaseEmbedView({ node }: NodeViewProps) {
   const pageId = node.attrs.pageId as string | null;
+  const pendingKey = node.attrs.pendingKey as string | null;
   const wrapperRef = useRef<HTMLDivElement | null>(null);
-  const { isLoading, isError } = useBaseQuery(pageId ?? "");
+  // Suppress the query while the slash command is still waiting for the
+  // server to assign a pageId — useBaseQuery would otherwise fire with
+  // an empty key and surface a transient error.
+  const { isLoading, isError } = useBaseQuery(pendingKey ? "" : pageId ?? "");
 
   useEffect(() => {
     const wrapper = wrapperRef.current;
@@ -67,7 +72,12 @@ export function BaseEmbedView({ node }: NodeViewProps) {
   }, [isLoading, isError, pageId]);
 
   let content: React.ReactNode;
-  if (!pageId) {
+  if (pendingKey) {
+    // Slash command inserted the embed and is awaiting the server's
+    // assigned pageId — render the same skeleton BaseTable shows on
+    // its own initial load so the swap is visually a no-op.
+    content = <BaseTableSkeleton />;
+  } else if (!pageId) {
     content = (
       <Box p="md">
         <Text c="red">Invalid base embed (missing page id)</Text>

apps/client/src/features/editor/components/slash-menu/menu-items.ts

@@ -53,6 +53,30 @@ import {
   YoutubeIcon,
 } from "@/components/icons";
 import api from "@/lib/api-client";
+import { notifications } from "@mantine/notifications";
+import type { Editor } from "@tiptap/core";
+
+// Resolve the position of a baseEmbed placeholder by its pendingKey.
+// Used by the Database slash command to patch in the real pageId once
+// the create-base API responds — positions may have shifted in the
+// interim from collab edits, undo/redo, or concurrent slash commands.
+function findBaseEmbedPlaceholderPos(
+  editor: Editor,
+  pendingKey: string,
+): number | null {
+  let foundPos: number | null = null;
+  editor.state.doc.descendants((node, pos) => {
+    if (
+      node.type.name === "baseEmbed" &&
+      node.attrs.pendingKey === pendingKey
+    ) {
+      foundPos = pos;
+      return false;
+    }
+    return true;
+  });
+  return foundPos;
+}
 
 const CommandGroups: SlashMenuGroupedItemsType = {
   basic: [
@@ -488,13 +512,57 @@ const CommandGroups: SlashMenuGroupedItemsType = {
         const parentPageId = editor.storage?.pageId as string | undefined;
         if (!parentPageId) return;
 
-        editor.chain().focus().deleteRange(range).run();
+        // Insert a placeholder embed at the slash position synchronously
+        // so (a) the position is established before any focus/selection
+        // drift during the await, and (b) the user sees a skeleton in
+        // the document instead of an empty gap. The API call then patches
+        // the real pageId into this exact node, identified by pendingKey.
+        const pendingKey =
+          typeof crypto !== "undefined" && "randomUUID" in crypto
+            ? crypto.randomUUID()
+            : `${Date.now()}-${Math.random()}`;
 
-        const res = await api.post<{ id: string }>("/bases/inline-embed", {
-          parentPageId,
-        });
+        editor
+          .chain()
+          .focus()
+          .deleteRange(range)
+          .insertBaseEmbed({ pageId: null, pendingKey })
+          .run();
 
-        editor.commands.insertBaseEmbed({ pageId: res.data.id });
+        try {
+          const res = await api.post<{ id: string }>("/bases/inline-embed", {
+            parentPageId,
+          });
+
+          const pos = findBaseEmbedPlaceholderPos(editor, pendingKey);
+          if (pos === null) return;
+          editor
+            .chain()
+            .command(({ tr }) => {
+              tr.setNodeMarkup(pos, undefined, {
+                pageId: res.data.id,
+                pendingKey: null,
+              });
+              return true;
+            })
+            .run();
+        } catch {
+          const pos = findBaseEmbedPlaceholderPos(editor, pendingKey);
+          if (pos !== null) {
+            editor
+              .chain()
+              .command(({ tr }) => {
+                const node = tr.doc.nodeAt(pos);
+                if (node) tr.delete(pos, pos + node.nodeSize);
+                return true;
+              })
+              .run();
+          }
+          notifications.show({
+            message: "Failed to create database",
+            color: "red",
+          });
+        }
       },
     },
     {

packages/editor-ext/src/lib/base-embed/base-embed.ts

@@ -8,7 +8,10 @@ export interface BaseEmbedOptions {
 declare module '@tiptap/core' {
   interface Commands<ReturnType> {
     baseEmbed: {
-      insertBaseEmbed: (attrs: { pageId: string }) => ReturnType;
+      insertBaseEmbed: (attrs: {
+        pageId: string | null;
+        pendingKey?: string | null;
+      }) => ReturnType;
     };
   }
 }
@@ -32,6 +35,16 @@ export const BaseEmbed = Node.create<BaseEmbedOptions>({
         renderHTML: (attrs) =>
           attrs.pageId ? { 'data-page-id': attrs.pageId } : {},
       },
+      // Transient marker set when the slash command inserts the embed
+      // before the server has assigned a pageId. The view renders a
+      // skeleton in this state. Cleared once the API responds and the
+      // real pageId is patched in. Not serialized — embeds saved with
+      // a pendingKey would orphan if the page were closed mid-request.
+      pendingKey: {
+        default: null,
+        parseHTML: () => null,
+        renderHTML: () => ({}),
+      },
     };
   },