Rename $lng to $language and add type hints

[Copilot]

Improved type safety and code clarity by renaming the ambiguous $lng parameter and adding complete type annotations.

Parameter renaming:

• Renamed $lng → $language across findByRegon(), findByNip(), findByKrs(), findById(), getCumulativeReport(), and getReport()

Type annotations:

• Added string type hints for $language parameter with default value "pl"
• Added return type declarations (: array, : void) to all methods
• Added missing type hints to validation methods and their parameters

Documentation:

• Updated PHPDoc blocks with proper @param string $language annotations
• Added description "Language code ('pl' or 'en')" for language parameters

// Before
public function findByRegon(string $regon, $lng = "pl"): array

// After  
public function findByRegon(string $regon, string $language = "pl"): array

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[jedrzejjarocki]

LGTM