Add is active to overridable entities and deactivation logic for page layouts (#19200)

- Replace soft-deletion (deletedAt) with isActive boolean for
overridable entities (tabs, widgets, viewFieldGroups, viewFields).
Standard entities are deactivated (isActive: false) when removed from
update payloads, while custom entities are hard-deleted.
- When a viewFieldGroup is deactivated/deleted, its viewFields are
reassigned to the next section by position (or null if none remain).
- Add isActive: true filters to viewFieldGroup and viewField API queries
so deactivated entities are excluded from responses.

Next: 
- fields-widget-upsert.service.ts should be refactored a bit
- Add restore logic

packages/twenty-server/src/engine/metadata-modules/flat-entity/constant/__tests__/__snapshots__/all-universal-flat-entity-properties-to-compare-and-stringify.constant.spec.ts.snap

@@ -174,6 +174,7 @@ exports[`ALL_UNIVERSAL_FLAT_ENTITY_PROPERTIES_TO_COMPARE_AND_STRINGIFY should ma
       "position",
       "deletedAt",
       "icon",
+      "isActive",
       "overrides",
     ],
     "propertiesToStringify": [
@@ -190,6 +191,7 @@ exports[`ALL_UNIVERSAL_FLAT_ENTITY_PROPERTIES_TO_COMPARE_AND_STRINGIFY should ma
       "universalConfiguration",
       "deletedAt",
       "conditionalDisplay",
+      "isActive",
       "overrides",
     ],
     "propertiesToStringify": [
@@ -299,6 +301,7 @@ exports[`ALL_UNIVERSAL_FLAT_ENTITY_PROPERTIES_TO_COMPARE_AND_STRINGIFY should ma
       "aggregateOperation",
       "viewFieldGroupUniversalIdentifier",
       "deletedAt",
+      "isActive",
       "universalOverrides",
     ],
     "propertiesToStringify": [
@@ -310,6 +313,7 @@ exports[`ALL_UNIVERSAL_FLAT_ENTITY_PROPERTIES_TO_COMPARE_AND_STRINGIFY should ma
       "name",
       "position",
       "isVisible",
+      "isActive",
       "deletedAt",
       "overrides",
     ],

packages/twenty-server/src/engine/metadata-modules/flat-entity/constant/all-entity-properties-configuration-by-metadata-name.constant.ts

@@ -373,6 +373,12 @@ export const ALL_ENTITY_PROPERTIES_CONFIGURATION_BY_METADATA_NAME = {
       toCompare: true,
       isOverridable: true,
     },
+    isActive: {
+      toCompare: true,
+      toStringify: false,
+      universalProperty: undefined,
+      isOverridable: false,
+    },
     deletedAt: {
       toStringify: false,
       universalProperty: undefined,
@@ -455,6 +461,12 @@ export const ALL_ENTITY_PROPERTIES_CONFIGURATION_BY_METADATA_NAME = {
       toStringify: false,
       universalProperty: 'viewUniversalIdentifier',
     },
+    isActive: {
+      toCompare: true,
+      toStringify: false,
+      universalProperty: undefined,
+      isOverridable: false,
+    },
     overrides: {
       toCompare: true,
       toStringify: true,
@@ -916,6 +928,12 @@ export const ALL_ENTITY_PROPERTIES_CONFIGURATION_BY_METADATA_NAME = {
       universalProperty: undefined,
       isOverridable: true,
     },
+    isActive: {
+      toCompare: true,
+      toStringify: false,
+      universalProperty: undefined,
+      isOverridable: false,
+    },
     overrides: {
       toCompare: true,
       toStringify: true,
@@ -966,6 +984,12 @@ export const ALL_ENTITY_PROPERTIES_CONFIGURATION_BY_METADATA_NAME = {
       toStringify: false,
       universalProperty: undefined,
     },
+    isActive: {
+      toCompare: true,
+      toStringify: false,
+      universalProperty: undefined,
+      isOverridable: false,
+    },
     overrides: {
       toCompare: true,
       toStringify: true,