feat(server): convert view to overridable entity (#21436)

## Context

Every entity created as a side effect of object creation must support
the overridable pattern (`isActive` + `overrides` + override routing)
before we can re-own side effects to their true application. Starting
with View.

viewField, viewFieldGroup, pageLayoutTab and pageLayoutWidget already
extend `OverridableEntity`. This PR brings `view` to the same pattern.

## What this does

- `ViewEntity` now extends `OverridableEntity<ViewOverrides>` (adds
`isActive` boolean + `overrides` jsonb). All editable view properties
are overridable; the 3 fieldMetadata foreign keys are converted to/from
universal identifiers like viewField's `viewFieldGroupId`.
- **Update**: mutations on a view not owned by the caller (e.g. standard
views like "All Companies") are written into `overrides` instead of
mutating the row. Reads merge overrides in
the DTO.
- **Delete/destroy**: views not owned by the caller are deactivated
(`isActive = false`) instead of deleted.
~~- **INDEX invariant**: `key = INDEX` views can only be created via
object-creation side effect. The API now rejects creating, deleting or
destroying INDEX views (object-deletion cascade is unaffected). This was
not really needed for this migration but was flagged during
implementation.~~
- **Front**: views with `isActive = false` are filtered out of the views
selector.
- Fast instance command adds the two columns
(`2-12-instance-command-fast-...-view-overridable-entity.ts`).

## Notes

- Custom (caller-owned) views behave exactly as before: direct updates,
soft delete.
- View-group side effects (kanban groups) are computed on the
override-merged view so overridden `mainGroupByFieldMetadataId` works.

packages/twenty-server/src/database/commands/upgrade-version-command/instance-commands.constant.ts

@@ -61,6 +61,7 @@ import { EncryptNonSecretApplicationVariableSlowInstanceCommand } from 'src/data
 import { MigrateAiModelPreferencesSlowInstanceCommand } from 'src/database/commands/upgrade-version-command/2-9/2-9-instance-command-slow-1799000010000-migrate-ai-model-preferences';
 import { DropIsCustomFromObjectAndFieldMetadataFastInstanceCommand } from 'src/database/commands/upgrade-version-command/2-12/2-12-instance-command-fast-1780579070012-drop-is-custom-from-object-and-field-metadata';
 import { DropEmailingDomainDriverColumnFastInstanceCommand } from 'src/database/commands/upgrade-version-command/2-11/2-11-instance-command-fast-1780926908000-drop-emailing-domain-driver-column';
+import { ViewOverridableEntityFastInstanceCommand } from 'src/database/commands/upgrade-version-command/2-12/2-12-instance-command-fast-1781114009075-view-overridable-entity';
 
 export const INSTANCE_COMMANDS = [
   AddViewFieldGroupIdIndexOnViewFieldFastInstanceCommand,
@@ -124,4 +125,5 @@ export const INSTANCE_COMMANDS = [
   EncryptNonSecretApplicationVariableSlowInstanceCommand,
   DropIsCustomFromObjectAndFieldMetadataFastInstanceCommand,
   DropEmailingDomainDriverColumnFastInstanceCommand,
+  ViewOverridableEntityFastInstanceCommand,
 ];