Scheduler refactor [utils]: functions, mixins, statistics, text

[markurtz]

Summary

This PR adds new utility modules for safe math function operations, object info extraction, and reorganizes to consolidate into the utils package.

Details

• Move statistics classes from objects to utils: Relocates DistributionSummary, Percentiles, RunningStats, StatusDistributionSummary, and TimeRunningStats from guidellm.objects.statistics to guidellm.utils.statistics
• Add new functions.py module: Implements defensive programming utilities including safe_getattr, safe_divide, safe_multiply, safe_add, safe_format_timestamp, and all_defined for handling None values and edge cases
• Add new mixins.py module: Provides InfoMixin class for standardized metadata extraction and object introspection across different class hierarchies
• Enhance text.py module: Adds comprehensive documentation, format_value_display function for consistent metric formatting, and improved text processing utilities
• Update import statements: Modifies all affected modules (benchmark, presentation) to import statistics classes from their new location in utils
• Remove deprecated objects package: Deletes the now-empty objects directory and associated test files
• Add comprehensive test coverage: Includes new test suites for functions.py, mixins.py, and statistics.py
• Update __init__.py exports: Adds new utility functions and classes to the main utils package exports for easy access

Test Plan

• Run the existing test suite to ensure no regressions from the statistics class relocation
• Execute new test files:
  • test_functions.py - Tests for safe operation utilities
  • test_mixins.py - Tests for InfoMixin functionality
  • test_statistics.py - Comprehensive tests for statistical analysis utilities
  • test_text.py - Tests for enhanced text processing functions

Related Issues

• Resolves #

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[Copilot]

Pull Request Overview

This PR implements a comprehensive refactor that consolidates statistical analysis utilities and introduces new defensive programming utilities for the GuideLLM scheduler system. The refactor moves statistics classes from the objects package to utils and adds new modules for safe operations, object introspection, and enhanced text processing.

• Relocates statistical analysis classes from guidellm.objects.statistics to guidellm.utils.statistics
• Adds new utility modules including functions.py for safe operations, mixins.py for object metadata extraction, and enhanced text.py with display formatting
• Introduces comprehensive test coverage for all new utility modules and maintains backward compatibility through import updates

Reviewed Changes

Copilot reviewed 15 out of 17 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
tests/unit/utils/test_text.py	Comprehensive test suite for text processing utilities including loading, filtering, and endless text generation
tests/unit/utils/test_statistics.py	Complete test coverage for statistical analysis utilities moved from objects package
tests/unit/utils/test_singleton.py	Test suite for singleton pattern implementations with thread safety validation
tests/unit/utils/test_registry.py	Tests for registry-based object discovery and registration system
tests/unit/utils/test_pydantic_utils.py	Test coverage for Pydantic model utilities and polymorphic serialization
tests/unit/utils/test_mixins.py	Tests for InfoMixin object introspection capabilities
tests/unit/utils/test_functions.py	Test suite for defensive programming utilities and safe operations
tests/unit/utils/test_auto_importer.py	Tests for automatic module importing and discovery mechanisms
Multiple source files	Implementation of new utility modules and import path updates for statistics classes

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[jaredoconnell]

Once my concerns and Samuel's concerns are addressed, I think this is ready for merging.
I want to confirm that we're okay with switching to Python 3.10. Otherwise these changes would need to be revised. I don't love the idea of moving to 3.10.