BUG: Series constructor loses date unit of Timestamps (original) (raw)

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Reproducible Example

pd.Timestamp("2024-01-01 00:00:00").unit 's' pd.Series([pd.Timestamp("2024-01-01 00:00:00")]).dt.unit 'ns'

### Issue Description

I would expect the Series to maintain the unit of 's'

### Expected Behavior

I would expect the Series to maintain the unit of 's'

### Installed Versions

'3.0.0.dev0+681.g434fda08cf'