Support Snowflake lambda functions

Snowflake recently gained support for [higher-order functions](https://medium.com/snowflake/snowflake-supports-higher-order-functions-dfa4b7682f7a) like [`TRANSFORM`](https://docs.snowflake.com/en/sql-reference/functions/transform) and [`FILTER`](https://docs.snowflake.com/en/sql-reference/functions/filter) which utilize a new [lambda function syntax](https://docs.snowflake.com/en/user-guide/querying-semistructured#lambda-expressions) similar to that of [Databricks](https://docs.databricks.com/en/sql/language-manual/sql-ref-lambda-functions.html) for which I [recently added support](https://github.com/sqlparser-rs/sqlparser-rs/pull/1257).

The two syntaxes look compatible so we can mostly reuse what we have. The one difference I noted is that Snowflake lambdas are permitted to specify types, e.g. `(x INT, y INT) -> (x + y)`.

先檢視現有的 Databricks lambda-function 支援和 PR #1257，接著將其與 Snowflake 的 lambda-expression 和 higher-order-function 語法進行比較。完成條件是 Snowflake lambda 能夠成功解析，包括具有明確型別的參數，例如 `(x INT, y INT) -> (x + y)`，且不破壞現有的相容語法。

由索引模型根據 Issue 內容生成。