Activity as standard object (#6219)

In this PR I layout the first steps to migrate Activity to a traditional
Standard objects

Since this is a big transition, I'd rather split it into several
deployments / PRs

<img width="1512" alt="image"
src="https://github.com/user-attachments/assets/012e2bbf-9d1b-4723-aaf6-269ef588b050">

---------

Co-authored-by: Charles Bochet <charles@twenty.com>
Co-authored-by: bosiraphael <71827178+bosiraphael@users.noreply.github.com>
Co-authored-by: Weiko <corentin@twenty.com>
Co-authored-by: Faisal-imtiyaz123 <142205282+Faisal-imtiyaz123@users.noreply.github.com>
Co-authored-by: Prateek Jain <prateekj1171998@gmail.com>

packages/twenty-front/src/modules/ui/layout/show-page/components/ShowPageActivityContainer.tsx

@@ -0,0 +1,31 @@
+import { RichTextEditor } from '@/activities/components/RichTextEditor';
+import { ActivityTargetableObject } from '@/activities/types/ActivityTargetableEntity';
+import { CoreObjectNameSingular } from '@/object-metadata/types/CoreObjectNameSingular';
+import styled from '@emotion/styled';
+
+const StyledShowPageActivityContainer = styled.div`
+  margin-top: ${({ theme }) => theme.spacing(2)};
+  width: 100%;
+`;
+export const ShowPageActivityContainer = ({
+  targetableObject,
+}: {
+  targetableObject: Pick<
+    ActivityTargetableObject,
+    'targetObjectNameSingular' | 'id'
+  >;
+}) => {
+  return (
+    <StyledShowPageActivityContainer>
+      <RichTextEditor
+        activityId={targetableObject.id}
+        fillTitleFromBody={false}
+        activityObjectNameSingular={
+          targetableObject.targetObjectNameSingular as
+            | CoreObjectNameSingular.Note
+            | CoreObjectNameSingular.Task
+        }
+      />
+    </StyledShowPageActivityContainer>
+  );
+};