Add pagination to search_files_by_name tool

[codegen-sh]

This PR adds pagination support to the search_files_by_name tool, similar to how it's implemented in the search tool. This addresses the issue where large result sets from file searches were causing long, unwieldy output.

Changes:

• Updated SearchFilesByNameResultObservation class to include pagination parameters (page, total_pages, total_files, files_per_page)
• Added a custom render() method to format the output with pagination information
• Modified the search_files_by_name function to support pagination with parameters for page number and files per page
• Updated the SearchFilesByNameInput class and SearchFilesByNameTool._run() method to accept and pass through pagination parameters
• Set default files_per_page to 50 (higher than search tool's default of 10 since filenames are shorter)
• Added sorting of results for consistent pagination

This change will make the tool more usable when dealing with large codebases that have many matching files.

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