Fixes https://github.com/twentyhq/twenty/issues/20524
## Problem
Adding (or renaming/removing) an option on a `SELECT` / `MULTI_SELECT`
field failed for fields whose object + field name combination is long,
surfacing to the user only as:
> Migration action 'update' for 'fieldMetadata' failed — Migration
execution failed.
The real underlying Postgres error was:
```
type "_personalInsurancePolicyOrQuote_insuranceCoverageClassification" already exists
ALTER TYPE "..."."_personalInsurancePolicyOrQuote_insuranceCoverageClassifications_enum"
RENAME TO "..._insuranceCoverageClassifications_enum_old"
```
## Root cause
PostgreSQL truncates identifiers to **63 bytes** (`NAMEDATALEN - 1`).
The enum type name
`_personalInsurancePolicyOrQuote_insuranceCoverageClassifications_enum`
is **69 chars**, so it was already stored truncated to 63
(`..._insuranceCoverageClassification` — the `_enum` suffix chopped
off).
Multi-select / select option changes go through the rename-and-recreate
path in `alterEnumValues`, which renames the enum to `<name>_old`. That
candidate is 73 chars → Postgres truncates it back to the **same 63-byte
string** as the source → `type "..." already exists`. The failure is
deterministic, so every retry on that field failed. The transaction
rolls back cleanly, leaving no `_old` artifacts behind.
The temporary column name (`<column>_old`) had the same latent bug for
very long field names.
## Fix
Add `buildTemporaryIdentifier(base, suffix)` to
`WorkspaceSchemaEnumManagerService`, which trims the base name so the
`_old` suffix survives within 63 bytes and stays distinct from the
original. Applied to both the temporary enum name and the temporary
column name.
The `_old` type/column are transient (dropped within the same
transaction), so the trimmed name only needs to fit and not collide —
which it now does.
## Test
Added `workspace-schema-enum-manager.service.spec.ts` reproducing the
exact failing object/field names. Both assertions (target identifier ≤
63 bytes; truncated source ≠ truncated target) fail on `main` and pass
with the fix.
## Recovery
No manual cleanup needed for affected workspaces — failed migrations
rolled back cleanly. Once deployed, option edits on long-named fields
work; the field remained fully usable in the meantime (only option
changes were blocked).
Thomas Trompette
22baf2c6c5