## Summary
- **Drop the `objectMetadata.dataSourceId` foreign key and index** via a
1-22 fast instance command — column kept nullable for data preservation
- **Delete `DataSourceService`, `DataSourceModule`, and
`DataSourceException`** — all code now uses `workspace.databaseSchema`
directly
- **Remove `IS_DATASOURCE_MIGRATED` feature flag** from default flags
and all branching logic
- **Simplify workspace/object creation pipelines** —
`WorkspaceManagerService`, `DevSeederService`, and the object creation
action handler no longer route through `DataSourceService`
- **Keep `DataSourceEntity` and the `dataSource` table** for historical
data — entity stripped of all ORM relations
## Summary
- Starts deprecation of the `core.dataSource` table by introducing a
dual-write system: `DataSourceService.createDataSourceMetadata` now
writes to both `core.dataSource` and `core.workspace.databaseSchema`
- Migrates read sites (`WorkspaceDataSourceService.checkSchemaExists`,
`WorkspaceSchemaFactory`, `MiddlewareService`,
`WorkspacesMigrationCommandRunner`) to read from
`workspace.databaseSchema` instead of querying the `dataSource` table
- Removes the unused `databaseUrl` field from `WorkspaceEntity` and
drops the column via migration
- Adds a 1.20 upgrade command to backfill `workspace.databaseSchema`
from `dataSource.schema` for existing workspaces
## Context
Deprecating legacy ObjectMetadata from cache in favor of flat entities.
Introducing utils to build byName/byNameSingular/byNamePlural in
isolated cases
## Next
- I had to introduce a util to build from flat to legacy
objectMetadataMaps, we should instead use flat maps directly when needed
(datasource, schema generation, etc)
- Deprecate metadata version in the cache
- Use the new cache strategy for flat entities with permissions and
feature flags and inject in the global datasource context
# This PR
- Addressing #3644
- Migrates the `DELETE /rest/*` endpoint to use TwentyORM
- Factorizes common middleware logic into a common module
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Co-authored-by: martmull <martmull@hotmail.fr>
Charles Bochet