SZ-ORM Procedural Macros - compile-time SQL validation & derive macros

Provides:

• sql_string! macro that validates SQL string literals at compile time. Errors like SELECT * FORM users or '; DROP TABLE are caught before the binary is built.
• #[derive(Schema)] — auto-generate table structure info from a struct.
• #[derive(Builder)] — auto-generate builder pattern code for a struct.

Usage

use sz_orm_macros::sql_string;

// Basic usage
let sql = sql_string!("SELECT * FROM users WHERE id = 1"); // ✅ compiles

// With parameter count check
let sql = sql_string!("SELECT * FROM users WHERE id = ?");
                     params: 1);                          // ✅ compiles

// ❌ compile error: missing FROM
let sql = sql_string!("SELECT * users WHERE id = 1");

// ❌ compile error: SQL injection detected
let sql = sql_string!("SELECT * FROM users WHERE name = 'x' OR '1'='1'");

// ❌ compile error: parameter count mismatch
let sql = sql_string!("SELECT * FROM users WHERE id = ?");
                     params: 2);

Derive macros

use sz_orm_macros::{Schema, Builder};

#[derive(Schema)]
#[table(name = "users")]
struct User {
    #[column(primary_key)]
    id: i64,
    name: String,
}

#[derive(Builder)]
struct Order {
    id: i64,
    total: f64,
}