[CI] Add `isort` and cancel on concurrency

[yaox12]

Description

1. Commit 806448592bb2d6ab867154665d1613f8f88f664d adds isort and move black and isort configs to pyproject.toml.
2. Commit 94385e2c573ea1b7fb4daf1e2be1bb8c8174ddbe add cancellation on concurrency to CI jobs to save CI resources.

Type of change

• [ ] Documentation change (change only to the documentation, either a fix or a new content)
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] Infra/Build change
• [ ] Code refactoring

Changes

Please list the changes introduced in this PR:

• Change A
• Change B

Checklist:

• [ ] I have read and followed the contributing guidelines
• [ ] The functionality is complete
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes

[greptile-apps[bot]]

Greptile Overview

Greptile Summary

This PR adds two infrastructure improvements: (1) isort integration for Python import sorting with configuration centralized in pyproject.toml alongside existing black settings, and (2) concurrency controls to automatically cancel outdated CI workflow runs when new commits are pushed to PRs, saving CI resources.

Key changes:

• Added isort pre-commit hook with profile="black" for compatibility
• Moved black configuration from command-line args to pyproject.toml
• Added concurrency groups to all three main workflows (build.yml, docs.yml, lint.yml) to cancel in-progress runs when superseded

The docs.yml workflow is also triggered via workflow_call from deploy_nightly_docs.yml on pushes to main. In those cases, github.event.pull_request.number will be empty, so the concurrency group falls back to github.ref, which still provides appropriate grouping behavior for main branch pushes.

Confidence Score: 5/5

• This PR is safe to merge with no blocking issues
• The changes are low-risk infrastructure improvements: adding import sorting tooling and workflow concurrency controls. All configurations are compatible (isort profile=black), and the concurrency grouping pattern is standard for GitHub Actions. The fallback behavior when github.event.pull_request.number is empty works correctly.
• No files require special attention

Important Files Changed

File Analysis

Filename	Score	Overview
.github/workflows/docs.yml	4/5	Added concurrency cancellation; may need adjustment for workflow_call trigger from deploy_nightly_docs
.pre-commit-config.yaml	5/5	Moved black args to pyproject.toml and added isort hook for import sorting
pyproject.toml	5/5	Added black and isort configurations with compatible settings (profile=black, line_length=100)

Sequence Diagram

sequenceDiagram
    participant Dev as Developer
    participant GH as GitHub
    participant Pre as Pre-commit Hooks
    participant CI as CI Workflows
    
    Dev->>Pre: git commit
    Pre->>Pre: Run black formatter
    Pre->>Pre: Run isort (import sorting)
    Pre->>Pre: Run other hooks
    Pre-->>Dev: Commit successful
    
    Dev->>GH: git push (new commit to PR)
    GH->>CI: Trigger workflows (build, lint, docs)
    
    Note over CI: Concurrency group checks
    CI->>CI: Cancel previous in-progress runs<br/>for same PR/workflow
    
    CI->>CI: Run new workflow instances
    CI-->>GH: Report results