[Call Recording] Add standard object (#21158)

Adds **Call Recording** as a first-class standard object (Twenty's
flat-metadata
standard-object system), with a hidden junction to calendar events and a
backfill
command for existing workspaces. Everything is gated behind the
`IS_CALL_RECORDING_ENABLED` feature flag.

### What's included
- **`CallRecording`**: audio/video files, transcript, status, recording
policy,
timing, external bot/recording ids. Label identifier is
`meetingOccurrenceKey`.
- **`CallRecordingCalendarEventAssociation`**: hidden junction linking a
recording
to a calendar event (dedupes one bot to many subscribers of the same
meeting).
- Full metadata graph via the flat-metadata builders: fields, indexes,
views,
  view fields/groups, record page layout, and navigation items.
- **Metadata-only reverse relation** on `CalendarEvent`: present in
standard
metadata, omitted from the TS entity class to avoid expanding recursive
  nested-insert types.
- **Upgrade command (2.9.0)** backfilling active/suspended workspaces:
  - Creates the full graph; idempotent (skips when it already exists).
- Moves a colliding custom `callRecording` object aside to
`callRecordingOld`
    (numeric suffix if that name is also taken).
- Navigation items (commands) are flag-gated by `universalIdentifier`,
so a custom object
    reusing the name is never gated.

### QA
Run locally against existing workspaces (with and without a name
collision) and a
freshly created workspace:
- [x] Backfill, collision: custom `callRecording` renamed to
`callRecordingOld`;
  standard graph created.
- [x] Backfill, no collision: standard graph created; unrelated custom
object untouched.
- [x] Idempotent: re-run is a no-op, with no duplicate metadata and
counts unchanged.
- [x] New workspace via `init()` produces an identical graph to the
backfill
  (`universalIdentifier` set-diff = 0).
- [x] Label identifier (`meetingOccurrenceKey`) holds position 0 in
non-widget views.
- [x] Nav items gated behind the feature flag; collision-renamed
object's nav
  expression re-pointed to its new name.
- [x] Unit tests cover collision name resolution and nav-gating logic.

packages/twenty-server/src/engine/workspace-manager/workspace-migration/constant/standard-object-icons.ts

@@ -8,6 +8,7 @@ export const STANDARD_OBJECT_ICONS = {
   calendarChannelEventAssociation: 'IconCalendar',
   calendarEventParticipant: 'IconCalendar',
   calendarEvent: 'IconCalendar',
+  callRecording: 'IconVideo',
   comment: 'IconMessageCircle',
   company: 'IconBuildingSkyscraper',
   dashboard: 'IconLayoutDashboard',