fix: resolve settings/usage chart crash and add ClickHouse usage event seeds (#19039)

## Summary

- **Fix settings/usage page crash**: The `GraphWidgetLineChart`
component used on `settings/usage` was crashing with "Instance id is not
provided and cannot be found in context" because it requires
`WidgetComponentInstanceContext` (for tooltip/crosshair component
states) which is only provided inside the widget system. Wraps the
standalone chart usages with the required context provider.
- **Avoid mounting `GraphWidgetLegend` when hidden**: The legend
component calls `useIsPageLayoutInEditMode()` which requires
`PageLayoutEditModeProviderContext` — another context only available
inside the widget system. Since the settings page passes
`showLegend={false}`, the fix conditionally unmounts the legend instead
of always mounting it with a `show` prop. Applied consistently across
all four chart types (line, bar, pie, gauge).
- **Add ClickHouse usage event seeds**: Generates ~400 realistic
`usageEvent` rows spanning the past 35 days with weighted user activity,
weekday/weekend patterns, and gradual ramp-up. Enables developers to see
the usage analytics page with data locally.

## Test plan

- [ ] Navigate to `settings/usage` — page should render without errors
- [ ] Verify the daily usage line chart displays correctly
- [ ] Navigate to a user detail page from the usage list
- [ ] Verify the user detail chart renders without errors
- [ ] Run `npx nx clickhouse:seed twenty-server` and confirm usage
events are seeded
- [ ] Verify chart legend still works correctly on dashboard widgets (no
regression)


Made with [Cursor](https://cursor.com)

packages/twenty-front/src/modules/settings/usage/components/UsageSectionSkeleton.tsx

@@ -0,0 +1,27 @@
+import { useContext } from 'react';
+
+import Skeleton, { SkeletonTheme } from 'react-loading-skeleton';
+import { Section } from 'twenty-ui/layout';
+import { ThemeContext } from 'twenty-ui/theme-constants';
+
+export const UsageSectionSkeleton = () => {
+  const { theme } = useContext(ThemeContext);
+
+  return (
+    <SkeletonTheme
+      baseColor={theme.background.tertiary}
+      highlightColor={theme.background.transparent.lighter}
+      borderRadius={4}
+    >
+      <Section>
+        <Skeleton width={160} height={16} />
+        <Skeleton
+          width="100%"
+          height={200}
+          borderRadius={8}
+          style={{ marginTop: 16 }}
+        />
+      </Section>
+    </SkeletonTheme>
+  );
+};