[FEAT] Adds SQL function modules (#2725)

This commit defines _SQLFunctions_ and _SQLModule_ which are responsible
for registering the Daft _FunctionExpr_ to be accessible from SQL
statements. It is basic and operates on-top-of _FunctionExpr_ .. that
is, without modifying it.


* SQLFunctions – map of names (String) to functions (SQLFunction)
* SQLFunction – wrapper type over _FunctionExpr_ to get the _validate_
method.
* SQLModule – holds necessary logic for a _FunctionExpr_ variant i.e.
NumericExpr, Utf8Expr, etc.

### Overview

```rust


/// SQLModule for FunctionExpr::Numeric
impl SQLModule for SQLModuleNumeric {
    fn register(parent: &mut SQLFunctions) {
        use FunctionExpr::Numeric as f;
        use NumericExpr::*;
        parent.add("abs", f(Abs));
        ....
    }
}

// register
let mut functions = SQLFunctions::new();
functions.register::<SQLModuleNumeric>();


// usage
let args = plan_args(args)
let func = functions.get("abs")
let expr = func.validate(args)?
```

### Future Considerations

* Remove SQLFunctions global lazy-static singleton; rather, make it
owned by (field of) the planner.
* Remove SQLFunction wrapper type in favor of extending
FunctionEvaluator trait
* Add arity checks once there are variants.
* Use multi-map to support function variants.
* Extract input validation duplication from _to_field_ and _evaluate_ to
be used by SQLPlanner as well.
* Derive a module from macros on the daft_dsl declarations

Cargo.toml

@@ -151,6 +151,7 @@ jaq-parse = "1.0.0"
 jaq-std = "1.2.0"
 num-derive = "0.3.3"
 num-traits = "0.2"
+once_cell = "1.19.0"
 pretty_assertions = "1.4.0"
 rand = "^0.8"
 rayon = "1.10.0"

src/daft-sql/Cargo.toml

@@ -4,9 +4,9 @@ common-error = {path = "../common/error"}
 daft-core = {path = "../daft-core"}
 daft-dsl = {path = "../daft-dsl"}
 daft-plan = {path = "../daft-plan"}
+once_cell = {workspace = true}
 pyo3 = {workspace = true, optional = true}
 sqlparser = {workspace = true}
-strum = {version = "0.26.3", features = ["derive"]}
 snafu.workspace = true
 
 [dev-dependencies]

src/daft-sql/src/error.rs

@@ -42,13 +42,6 @@ impl From<ParserError> for PlannerError {
         PlannerError::SQLParserError { source: value }
     }
 }
-impl From<strum::ParseError> for PlannerError {
-    fn from(value: strum::ParseError) -> Self {
-        PlannerError::ParseError {
-            message: value.to_string(),
-        }
-    }
-}
 
 impl PlannerError {
     pub fn column_not_found<A: Into<String>, B: Into<String>>(column_name: A, relation: B) -> Self {