Use absolute imports

[TomeHirata]

No description provided.

[Copilot]

Pull Request Overview

This PR enforces absolute imports throughout the dte_adj package by adding Ruff linting rules and converting all relative imports to absolute imports.

• Adds Ruff configuration to ban relative imports (TID252 rule)
• Converts all relative imports to absolute imports using the dte_adj package prefix
• Updates import formatting in __init__.py for better readability

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pyproject.toml	Adds Ruff linting configuration to enforce absolute imports
dte_adj/stratified.py	Converts relative import of base module to absolute import
dte_adj/simple.py	Converts relative import of stratified module to absolute import
dte_adj/local.py	Converts relative imports of stratified and util modules to absolute imports
dte_adj/init.py	Converts all relative imports to absolute imports and improves formatting

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