Enhance company search API to support legal name filtering

We are improving the company search API by allowing users to search specifically by legal name. This feature will enable more precise queries for cases where users need to match only the official registered company name rather than variations or trade names.

🔹 Why?

• Provides more accurate results when searching for officially registered companies.

• Helps users differentiate between legal names and brand/trade names.

• Supports compliance and verification use cases where legal name matching is required.

• Improves data accuracy in lead enrichment and company identification workflows.

🔹 How it works?

• Add a query parameter to the existing search endpoint (e.g., ?legal_name_only=true).

• Ensure that when this parameter is set, only exact matches to the legal name are returned.

• Optimize Elasticsearch queries to prioritize legal names in results.

• Validate results to ensure correct filtering and minimal false positives.

• Update API documentation to reflect the new filtering option.