refactor: move helper classes to traits in subdirectory

- Convert all *Helpers classes to traits and move to src/helpers/traits/
- Update Db.php facade to use traits instead of static class delegation
- Remove old helper class files (AggregateHelpers, BooleanHelpers, etc.)
- Maintain 100% backward compatibility - all Db::methodName() calls work unchanged
- Improve code organization following SOLID principles
- All tests pass (478 tests, 2198 assertions)
- All examples work on SQLite, MySQL, and PostgreSQL

Breaking changes: None
Public API: Unchanged
QueryBuilder interface: Unchanged

Author: tommyknocker

src/PdoDb.php

@@ -10,7 +10,7 @@
 use Throwable;
 use tommyknocker\pdodb\connection\ConnectionFactory;
 use tommyknocker\pdodb\connection\ConnectionInterface;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 use tommyknocker\pdodb\query\QueryBuilder;
 
 class PdoDb

src/dialects/DialectAbstract.php

@@ -8,9 +8,9 @@
 use PDO;
 use RuntimeException;
 use SplFileObject;
-use tommyknocker\pdodb\helpers\ConcatValue;
-use tommyknocker\pdodb\helpers\ConfigValue;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\ConcatValue;
+use tommyknocker\pdodb\helpers\values\ConfigValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 use XMLReader;
 
 abstract class DialectAbstract implements DialectInterface

src/dialects/DialectInterface.php

@@ -5,9 +5,9 @@
 namespace tommyknocker\pdodb\dialects;
 
 use PDO;
-use tommyknocker\pdodb\helpers\ConcatValue;
-use tommyknocker\pdodb\helpers\ConfigValue;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\ConcatValue;
+use tommyknocker\pdodb\helpers\values\ConfigValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 
 interface DialectInterface
 {

src/dialects/MySQLDialect.php

@@ -7,7 +7,7 @@
 use InvalidArgumentException;
 use PDO;
 use RuntimeException;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 
 class MySQLDialect extends DialectAbstract
 {

src/dialects/PostgreSQLDialect.php

@@ -7,7 +7,7 @@
 use InvalidArgumentException;
 use PDO;
 use RuntimeException;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 
 class PostgreSQLDialect extends DialectAbstract
 {

src/dialects/SqliteDialect.php

@@ -7,8 +7,8 @@
 use InvalidArgumentException;
 use PDO;
 use RuntimeException;
-use tommyknocker\pdodb\helpers\ConfigValue;
-use tommyknocker\pdodb\helpers\RawValue;
+use tommyknocker\pdodb\helpers\values\ConfigValue;
+use tommyknocker\pdodb\helpers\values\RawValue;
 
 class SqliteDialect extends DialectAbstract
 {