BUG: .loc with DateTimeIndex allows day first string for stop in slice, but not start

[WillAyd]

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Reproducible Example

>>> ser = pd.Series(range(15), index=pd.date_range(start="2024-01-01", freq="D", periods=15))
>>> ser.loc["1/10/2024":"1/14/2024"]  # ok I suppose
2024-01-10     9
2024-01-11    10
2024-01-12    11
2024-01-13    12
2024-01-14    13
Freq: D, dtype: int64

>>> ser.loc["1/10/2024":"14/1/2024"] # huh? ok...
2024-01-10     9
2024-01-11    10
2024-01-12    11
2024-01-13    12
2024-01-14    13
Freq: D, dtype: int64

>>> ser.loc["10/1/2024":"14/1/2024"]
Series([], Freq: D, dtype: int64)

### Issue Description

I am not really sure what the expectations are for handling non-ISO strings as an indexer for a DTI. In the examples above it seems acceptable for the /stop/ argument in the slice to have the day first but the /start/ argument does not assume this

### Expected Behavior

Not sure - maybe we should just disallow non-ISO string formats?

### Installed Versions

'3.0.0.dev0+681.g434fda08cf'