JsonSource should support path expressions

# JsonSource should support path expressions

# Scenario

- If I have defined a structure like the following:
```sql
struct Person {
name:String,
age: Int,
sex: String
}
```
- I should be able to specify a projection like so:
```scala
withProjection("person.name", "person.age")
```

- The above returns scalar values for name and age.
- Likewise I think it should work for **withPredicate**
- Jackson has has processor for drilling into nested types using path expressions which are similar to XPath
- You could put forward a case that this syntax should be the language for other formats that support nested types, Avro, Parquet and Orc

Look at the JsonSource class and its withProjection and withPredicate methods. Understand how Jackson's path expression processor works for nested types. Check similar handling in Avro, Parquet, and Orc formats within the SDK. The goal is to extend support for path expressions like 'person.name' to return scalar values from nested structures.

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