Refactor expectation registration

[ryanseq-gyg]

Description

This PR refactors the expectation registration system to address the growing size of the DataFrameExpectationsSuite class (previously 800+ lines of boilerplate). The new architecture replaces manual method definitions with dynamic generation from a central registry, while maintaining full IDE type-ahead support through auto-generated stub files.

Key Changes:

1. Dynamic Method Generation

• Replaced 800+ lines of repetitive expect_* methods with a getattr-based approach
• Methods are now generated dynamically from registry metadata
• User-facing API remains unchanged—backward compatible

2. IDE Support via Type Stubs

• Auto-generated expectations_suite.pyi provides full IntelliSense/autocomplete support
• Generated by generate_suite_stubs.py from registry metadata
• Integrated with pre-commit hooks to ensure stubs stay in sync

3. Improved Tooling

• Updated documentation system to read from registry instead of runtime inspection
• Sanity checks validate registry, stubs, tests, and suite methods
• All tooling uses registry as single source of truth

4. Updated register_expectation decorator
   All @register_expectation decorators now require complete metadata:

@register_expectation(
    expectation_name="ExpectationValueGreaterThan",
    category=ExpectationCategory.COLUMN,
    subcategory=ExpectationSubcategory.NUMERICAL,
    pydoc="Check if values in a column are greater than a specified value",
    params=["column_name", "value"],
    params_doc={
        "column_name": "The name of the column to check",
        "value": "The value to compare against"
    },
    param_types={"column_name": str, "value": Union[int, float]}
)

Checklist

• Tests have been added in the prescribed format
• Commit messages follow Conventional Commits format
• Pre-commit hooks pass locally

[Copilot]

Pull Request Overview

This PR refactors the expectation registration system to use Pydantic for metadata validation and introduces automatic stub file generation for IDE autocomplete support. The main changes include:

• Addition of Pydantic dependency for metadata validation
• Dynamic method generation in DataFrameExpectationsSuite using __getattr__
• Automatic .pyi stub file generation for IDE support
• Enhanced expectation registry with metadata tracking using enums and Pydantic models

Reviewed Changes

Copilot reviewed 19 out of 20 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
uv.lock	Adds pydantic 2.12.4 and dependencies (annotated-types, pydantic-core, typing-inspection)
pyproject.toml	Adds pydantic>=2.12.4 dependency
dataframe_expectations/expectations/expectation_registry.py	Adds ExpectationMetadata model, enums for categories, and metadata tracking
dataframe_expectations/expectations_suite.py	Refactors to use dynamic method generation via getattr
scripts/generate_suite_stubs.py	New script to generate .pyi stub files from registry metadata
dataframe_expectations/expectations_suite.pyi	Auto-generated type stubs for IDE autocomplete
scripts/sanity_checks.py	Updates to validate stub file and use registry for suite methods
tests/expectations_helper_classes/test_expectation_registry.py	Updates test registrations with new required metadata parameters
docs/source/adding_expectations.rst	Updated documentation for new registration API
.pre-commit-config.yaml	Adds check for stub file freshness

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