(feature) adds support for lazy importing of rows

[pusherman]

Adds support for lazy importing of rows to handle very large import files quickly and memory efficiently

[Copilot]

Pull Request Overview

This PR adds lazy importing functionality to handle very large import files efficiently by using Laravel's LazyCollection instead of loading all data into memory at once.

• Introduces importLazy() method that returns a LazyCollection for memory-efficient processing
• Refactors existing import logic into reusable methods to support both eager and lazy loading
• Adds comprehensive test coverage for the new lazy import functionality

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
tests/LazyImportTest.php	Adds test cases for lazy import functionality with and without callback mapping
src/Importable.php	Implements lazy import method, refactors row normalization logic, and adds generator-based sheet processing

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[Copilot]

The error message should be more descriptive and use a specific exception type. Consider using InvalidArgumentException with a message like 'Transpose functionality is not compatible with lazy importing. Use import() method instead.'

Suggested change

	throw new \Exception('Transposing is not supported with lazy import.');
	// Transpose functionality is not compatible with lazy importing
	throw new \InvalidArgumentException('Transpose functionality is not compatible with lazy importing. Use import() method instead.');

[Copilot]

The cell processing logic is duplicated between importSheet() and importSheetGenerator(). Consider extracting this into a private method like processCellValue(Cell $cell) to reduce code duplication.

Suggested change

	}, $rowAsObject->getCells());
	$row = array_map([$this, 'processCellValue'], $rowAsObject->getCells());

[Copilot]

The normalizeRow method lacks proper PHPDoc documentation. It should include @param and @return annotations with type information and descriptions for the reference parameters.

Suggested change

	* @return array|null
	* @param int $k The current row index.
	* @param array $row The row data to normalize.
	* @param array &$headers Reference to the headers array, updated when header row is encountered.
	* @param int &$count_header Reference to the header count, updated when header row is encountered.
	*
	* @return array|null Returns an associative array if headers exist, the raw row if not, or null to skip processing.