refactor(server): unify the two metadata override mechanisms into one (#22417)

## Unify the two metadata override mechanisms into one

Twenty had **two** override mechanisms:

- **`standardOverrides`** — a bespoke JSONB column on
`objectMetadata`/`fieldMetadata` with typed DTOs and a per-locale
`translations` map, resolved by two i18n-aware resolvers.
- **`OverridableEntity.overrides`** — a flat, registry-driven JSONB blob
on view / view-field / view-field-group / command-menu-item /
page-layout-tab / page-layout-widget, resolved by a plain spread.

This PR collapses them into **one** concept: a single `overrides` blob,
one registry-driven overridable set, one i18n-aware read path, and one
write path (`computeMetadataOverridesBlob`, extracted in #22404).

Object/field **stay on `SyncableEntity`** (not reparented to
`OverridableEntity`) so their `isActive` default stays **FALSE** — this
sidesteps the `isActive` default conflict entirely.

### GraphQL breaking change (accepted)

The `standardOverrides` field is **removed** with no deprecation alias —
`overrides` (a `JSON` scalar) is exposed instead on `Object` and
`Field`. Product confirmed negligible external usage; the front-end has
no hand-written consumer (only generated types), which are regenerated
here.

### Commit structure (reviewable commit-by-commit)

1. **Unified resolver + parity harness** —
`resolveEffectiveEntityProperty` is a strict superset of the three
legacy resolvers; a corpus parity spec compares it against a *frozen
reference* of the old logic across every locale, `isStandardApp` branch
and override shape.
2. **Registry-driven** — object/field presentation props tagged
`isOverridable` + `translatable`; the overridable/translatable sets are
derived from the registry (a test asserts they equal the legacy
hardcoded lists).
3. **Rename + swap + delete** — `standardOverrides` → `overrides` across
entities, DTOs, flat/universal types, producers, the ~12
resolve/write/create/sync call sites, mocks and specs; the reconciler's
two compare entries collapse to one; the three legacy resolvers, both
DTOs and the hardcoded constants/types are deleted.
4. **Migration (zero-downtime, two-phase)** — split across two releases
so a rolling deploy never drops a column a previous-release pod still
`SELECT`s:
   - **2.19 fast** — add the `overrides` column (schema only).
- **2.19 slow** — backfill `overrides` from `standardOverrides` in
`runDataMigration` (kept out of the schema transaction so the bulk write
doesn't hold the ACCESS EXCLUSIVE lock; skipped on fresh installs, which
have no data to copy).
- **2.20 fast** — drop the legacy `standardOverrides` column (gated by
`TWENTY_NEXT_VERSIONS`, so it stays dormant until the instance reaches
2.20).
5. **Front/client-SDK regen** — regenerated metadata GraphQL types.
6. **Integration specs + i18n** — updated the standard object/field
update integration specs + snapshots, and the reworded validator message
catalog entry.

### Rolling-deploy safety

`standardOverrides` is retained through 2.19 and only dropped in 2.20,
mirroring the codebase's deferred-drop convention
(`isUIReadOnly`/`isCustom`). During the 2.19 rollout both columns exist,
so old and new pods coexist without "column does not exist" errors. The
backfill lives in a slow `runDataMigration` (per the
`no-data-mutation-in-fast-instance-command` rule) so it doesn't stall
reads.

### `isActive` guard

The migration never reads or writes `isActive`; the backfill asserts the
active-row count is unchanged and aborts otherwise. Verified on a real
DB: apply + revert preserves the blob **and** the nested `translations`
map, with `isActive` counts identical before/after.

### Verification (local)

- `nx typecheck twenty-server` + `nx typecheck twenty-front` — green
- `nx lint:diff-with-main twenty-server` (oxlint `--type-aware` + oxfmt)
— green
- `nx test twenty-server` — green (unit + parity + registry + migration
tests)
- `nx run twenty-server:test:integration:with-db-reset` — green
- `database:reset` applies the 2.19 phases and leaves **both** columns
present (2.20 drop stays dormant); backfill + revert round-trip verified
on a real DB
- Metadata integration suites (standard object/field update, application
sync) pass end-to-end against the two-column schema
- Metadata GraphQL types regenerated against a booted server; zero
`standardOverrides` references remain in application code (only the
migration commands + the legacy schema baseline)

---------

Co-authored-by: prastoin <paul@twenty.com>

packages/twenty-server/src/engine/metadata-modules/page-layout/services/page-layout-update.service.ts

@@ -36,7 +36,7 @@ import {
 } from 'src/engine/metadata-modules/page-layout/exceptions/page-layout.exception';
 import { fromFlatPageLayoutWithTabsAndWidgetsToPageLayoutDto } from 'src/engine/metadata-modules/page-layout/utils/from-flat-page-layout-with-tabs-and-widgets-to-page-layout-dto.util';
 import { isCallerOverridingEntity } from 'src/engine/metadata-modules/utils/is-caller-overriding-entity.util';
-import { resolveFlatEntityOverridableProperties } from 'src/engine/metadata-modules/utils/resolve-flat-entity-overridable-properties.util';
+import { resolveEffectiveEntity } from 'src/engine/metadata-modules/utils/resolve-effective-entity.util';
 import { sanitizeOverridableEntityInput } from 'src/engine/metadata-modules/utils/sanitize-overridable-entity-input.util';
 import { ViewService } from 'src/engine/metadata-modules/view/services/view.service';
 import { WorkspaceMigrationBuilderException } from 'src/engine/workspace-manager/workspace-migration/exceptions/workspace-migration-builder-exception';
@@ -283,9 +283,7 @@ export class PageLayoutUpdateService {
       .filter(isDefined)
       .filter((tab) => tab.pageLayoutId === existingPageLayout.id);
 
-    const resolvedExistingTabs = existingTabs.map(
-      resolveFlatEntityOverridableProperties,
-    );
+    const resolvedExistingTabs = existingTabs.map(resolveEffectiveEntity);
 
     const {
       toCreate: entitiesToCreate,
@@ -561,9 +559,7 @@ export class PageLayoutUpdateService {
       flatPageLayoutWidgetMaps,
     });
 
-    const resolvedExistingWidgets = existingWidgets.map(
-      resolveFlatEntityOverridableProperties,
-    );
+    const resolvedExistingWidgets = existingWidgets.map(resolveEffectiveEntity);
 
     const {
       toCreate: entitiesToCreate,