Deprecate Expr for functions that take only specific literals

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

This is the original comment that leads to this issue: https://github.com/apache/datafusion-python/pull/1484#discussion_r3079835791

**Describe the solution you'd like**

Add deprecation warnings, then remove`Expr` type hint in a later release

**Describe alternatives you've considered**

Leave as is

**Additional context**

We only allow specific values, so we can check them at the function invocation.

從 PR #1484 連結的討論開始，確認哪些函式只接受特定的字面值。追蹤這些函式的定義及其 type hints，然後檢查其他地方如何處理棄用警告。當受影響的 type hints 發出棄用警告，且預期的後續移除已記錄在文件中或由測試涵蓋時，即視為完成。

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