fix: autogrow input sizing + surface nested error details in upgrade command (#18796)

## Summary

### Fix 1: Autogrow input unclickable when value is empty string
- Fixes the last name input on the Person record show page being
unclickable on regular screens

### Fix 2: Surface nested migration errors in add-missing-system-fields
command
- `AddMissingSystemFieldsToStandardObjectsCommand` calls
`workspaceMigrationRunnerService.run()` directly and was re-throwing
`WorkspaceMigrationRunnerException` without reading its nested `errors`
- Extracted `getNestedErrorMessages()` helper (reused by both
`isUniqueViolationError` and `enrichErrorMessage`)
- Both catch sites now call `enrichErrorMessage()` before re-throwing,
appending nested error details to the message

**Before:**
```
ERROR [UpgradeCommand] Error in workspace ...: Migration action 'create' for 'fieldMetadata' failed
ERROR [UpgradeCommand] undefined
```

**After:**
```
ERROR [UpgradeCommand] Error in workspace ...: Migration action 'create' for 'fieldMetadata' failed (metadata: duplicate key value violates unique constraint "...")
```

## Test plan
- [x] Lint passes
- [x] Typecheck passes
- [x] Verify upgrade command errors now include nested error details
- [x] Verify autogrow input is clickable when value is empty string

packages/twenty-front/src/modules/ui/input/components/TextInput.tsx

@@ -1,4 +1,5 @@
 import { InputErrorHelper } from '@/ui/input/components/InputErrorHelper';
+import { isNonEmptyString } from '@sniptt/guards';
 import { isDefined } from 'twenty-shared/utils';
 import { InputLabel } from '@/ui/input/components/InputLabel';
 import { css } from '@linaria/core';
@@ -459,7 +460,7 @@ const TextInputWithAutoGrowWrapper = forwardRef<
       {props.autoGrow ? (
         <StyledAutogrowWrapper
           sizeVariant={props.sizeVariant}
-          node={props.value ?? props.placeholder}
+          node={isNonEmptyString(props.value) ? props.value : props.placeholder}
         >
           <TextInputComponent
             // oxlint-disable-next-line react/jsx-props-no-spreading