fix: restructure navigationMenuItem type migration for safe upgrade path (#18722)

## Summary

- Restructures the `navigationMenuItem.type` column migration to follow
the established 3-step safe upgrade pattern (used for webhooks, files,
etc.)
- The previous migration added `type` as `NOT NULL DEFAULT 'VIEW'` with
a CHECK constraint in one step, which incorrectly assigned `VIEW` to all
existing rows regardless of their actual type (folders, records, links,
objects)
- Now: (1) migration adds column as nullable, (2) upgrade command
backfills correct type from existing columns (`viewId`,
`targetRecordId`, `targetObjectMetadataId`, `link`) and cleans
conflicting columns, (3) shared utility applies `NOT NULL` + `CHECK`
constraint

### Changes

**Modified:**
- `1773681736596-add-type-to-navigation-menu-item.ts` -- adds column as
nullable, no DEFAULT, no CHECK
- `navigation-menu-item.entity.ts` -- removed `default:
NavigationMenuItemType.VIEW` from column decorator
- `upgrade.command.ts` / `1-19-upgrade-version-command.module.ts` --
wired new command

**Created:**
- `1773681736596-makeNavigationMenuItemTypeNotNull.util.ts` -- shared
utility applying NOT NULL + CHECK constraint
- `1773822077682-make-navigation-menu-item-type-not-null.ts` --
migration calling the util with savepoint (succeeds on fresh installs,
swallows error on upgrades with NULL data)
- `1-19-backfill-navigation-menu-item-type.command.ts` -- upgrade
command that backfills type, cleans conflicting columns, then applies
constraints via the shared utility

### Execution flow

**Existing deployments (upgrade):**
1. TypeORM migration adds nullable `type` column, drops old CHECK
2. Savepoint migration fails gracefully (existing rows have NULL type)
3. 1-18 favorites migration creates items WITH correct type
4. 1-19 backfill command infers type for remaining NULL rows, cleans
conflicting columns, applies NOT NULL + CHECK

**Fresh installs:**
1. TypeORM migration adds nullable `type` column
2. Savepoint migration succeeds immediately (no data, constraints apply
cleanly)

## Test plan

- [x] `npx nx typecheck twenty-server` passes
- [x] `npx nx lint:diff-with-main twenty-server` passes
- [x] `npx nx test twenty-server` passes (477 suites, 4297 tests)
- [ ] Verify fresh database setup with `npx nx database:reset
twenty-server` applies both migrations and constraints correctly
- [ ] Verify upgrade path: existing navigation menu items get correct
type backfilled based on their columns

Made with [Cursor](https://cursor.com)

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

@@ -29,9 +29,10 @@ import { MigrateWorkflowSendEmailAttachmentsCommand } from 'src/database/command
 import { MigrateWorkspacePicturesCommand } from 'src/database/commands/upgrade-version-command/1-18/1-18-migrate-workspace-pictures.command';
 import { AddMissingSystemFieldsToStandardObjectsCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-add-missing-system-fields-to-standard-objects.command';
 import { BackfillMessageChannelMessageAssociationMessageFolderCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-backfill-message-channel-message-association-message-folder.command';
+import { BackfillMissingStandardViewsCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-backfill-missing-standard-views.command';
+import { BackfillNavigationMenuItemTypeCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-backfill-navigation-menu-item-type.command';
 import { BackfillSystemFieldsIsSystemCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-backfill-system-fields-is-system.command';
 import { FixInvalidStandardUniversalIdentifiersCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-fix-invalid-standard-universal-identifiers.command';
-import { BackfillMissingStandardViewsCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-backfill-missing-standard-views.command';
 import { SeedServerIdCommand } from 'src/database/commands/upgrade-version-command/1-19/1-19-seed-server-id.command';
 import { BackfillCommandMenuItemsCommand } from 'src/database/commands/upgrade-version-command/1-20/1-20-backfill-command-menu-items.command';
 import { BackfillPageLayoutsCommand } from 'src/database/commands/upgrade-version-command/1-20/1-20-backfill-page-layouts.command';
@@ -83,6 +84,7 @@ export class UpgradeCommand extends UpgradeCommandRunner {
     protected readonly addMissingSystemFieldsToStandardObjectsCommand: AddMissingSystemFieldsToStandardObjectsCommand,
     protected readonly backfillMessageChannelMessageAssociationMessageFolderCommand: BackfillMessageChannelMessageAssociationMessageFolderCommand,
     protected readonly backfillMissingStandardViewsCommand: BackfillMissingStandardViewsCommand,
+    protected readonly backfillNavigationMenuItemTypeCommand: BackfillNavigationMenuItemTypeCommand,
     protected readonly fixRoleAndAgentUniversalIdentifiersCommand: FixInvalidStandardUniversalIdentifiersCommand,
     protected readonly seedServerIdCommand: SeedServerIdCommand,
 
@@ -133,10 +135,12 @@ export class UpgradeCommand extends UpgradeCommandRunner {
       this.addMissingSystemFieldsToStandardObjectsCommand,
       this.backfillMessageChannelMessageAssociationMessageFolderCommand,
       this.backfillMissingStandardViewsCommand,
+      this.backfillNavigationMenuItemTypeCommand,
       this.seedServerIdCommand,
     ];
 
     const commands_1200: VersionCommands = [
+      this.backfillNavigationMenuItemTypeCommand,
       this.migrateRichTextToTextCommand,
       this.backfillCommandMenuItemsCommand,
       this.backfillPageLayoutsCommand,