feat(settings): move settings chrome into a single rounded card (#21131)

## What

Replaces `SubMenuTopBarContainer` with a settings-specific
`SettingsPageLayout` that puts the whole page chrome — breadcrumb,
centered title, actions, an optional secondary bar (tabs or wizard
step), and the 760px body — inside **one rounded card**, with
`SidePanelForDesktop` as a sibling. Title, tabs and body content share
one centered vertical axis at every card width.

Supersedes #21122. One PR, no feature flag.

## New components (`@/settings/components/layout/`)

- **SettingsPageLayout** — owns the rounded card + side-panel sibling,
`useCommandMenuHotKeys`, mobile command menu
- **SettingsPageHeader** — breadcrumb · centered title · actions in a
symmetric `1fr auto 1fr` grid (symmetric padding throughout)
- **SettingsSecondaryBar** — the secondary row, bracketed by top +
bottom borders
- **SettingsTabBar** — centered tabs reusing `activeTabIdComponentState`
+ `TabListFromUrlOptionalEffect` for URL-hash sync (does not touch the
shared `TabList`)
- **SettingsWizardStepBar** — back arrow · "N. Label" · optional
trailing slot

## Migrations

- Bulk rename across ~80 call sites (`SubMenuTopBarContainer` →
`SettingsPageLayout`); old component deleted.
- 5 tab pages (AI, APIs & Webhooks, Applications, Members, Role) + the
Data Model object-detail page render their tabs in `secondaryBar`
(object-detail keeps "See records" / "New Field" in the header actions).
- The 2 role object-level steps render the wizard step bar with working
back navigation.
- Accounts consolidated into **General / Emails / Calendars** tabs;
standalone `SettingsAccountsEmails` / `SettingsAccountsCalendars` pages
+ routes + stories removed. `SettingsPath.AccountsEmails` /
`AccountsCalendars` now resolve to `accounts#emails` /
`accounts#calendars`, so existing `getSettingsPath()` links deep-link to
the right tab via the existing hash sync — no call-site changes.

## Verification

- `nx typecheck twenty-front` and `nx lint twenty-front` both clean.
- Browser (logged-in workspace): title / tab / body / card centers align
on a single axis at multiple widths — width-invariant, so alignment
holds when the AI side panel (a sibling) shrinks the card. Rounded card
with even gaps on all four sides; tab row bracketed by two 1px lines;
no-tab pages render header → body with no lines; wizard back navigation
works; `…/accounts#emails` opens the Emails tab.

The shared `PageHeader` and `TabList` are untouched. The settings side
panel itself isn't wired to open yet — that's a follow-up PR.

packages/twenty-front/src/modules/settings/developers/components/SettingsDevelopersWebhookForm.tsx

@@ -9,7 +9,7 @@ import { SettingsTextInput } from '@/ui/input/components/SettingsTextInput';
 import { TextArea } from '@/ui/input/components/TextArea';
 import { ConfirmationModal } from '@/ui/layout/modal/components/ConfirmationModal';
 import { useModal } from '@/ui/layout/modal/hooks/useModal';
-import { SubMenuTopBarContainer } from '@/ui/layout/page/components/SubMenuTopBarContainer';
+import { SettingsPageLayout } from '@/settings/components/layout/SettingsPageLayout';
 import { Trans, useLingui } from '@lingui/react/macro';
 import { SettingsPath } from 'twenty-shared/types';
 import {
@@ -72,13 +72,12 @@ export const SettingsDevelopersWebhookForm = ({
   return (
     // oxlint-disable-next-line react/jsx-props-no-spreading
     <FormProvider {...formConfig}>
-      <SubMenuTopBarContainer
+      <SettingsPageLayout
         title={getTitle()}
-        reserveTitleSpace
         links={[
           {
             children: t`Workspace`,
-            href: getSettingsPath(SettingsPath.Workspace),
+            href: getSettingsPath(SettingsPath.General),
           },
           {
             children: t`APIs & Webhooks`,
@@ -194,7 +193,7 @@ export const SettingsDevelopersWebhookForm = ({
             </Section>
           )}
         </SettingsPageContainer>
-      </SubMenuTopBarContainer>
+      </SettingsPageLayout>
       {!isCreationMode && (
         <ConfirmationModal
           confirmationPlaceholder={t`yes`}