Add ELM migrations commands

[bhuvanshahMSFT]

What

• Add az devops migrations command group for ELM (ADO -> GitHub Proxima) migrations.
• Include create/status/list/pause/resume/migrate/cutover/abandon flows.
• Add validations and formatting.
• Add --agent-pool-name and --skip-validation to create.
• Normalize optional create fields (trim, omit empty values).
• Update help and unit tests for optional fields.

Why

• Enable scripted live migration workflows via Azure DevOps CLI extension.

Testing

• pytest azext_devops/tests/latest/migration/test_migration.py

Notes

• Uses devfabric endpoint; --org is used for auth resolution.
• Target repo URL must be https://microsoft.ghe.com/OrgName/RepoName.
• Full pytest currently has unrelated failures in boards/repos auth validation tests.

[GeoffCoxMSFT]

@v-anvashist @V-hmusukula @v-soujanya I had trouble finding your MSFT aliases, so please let me (gcox) know you've received this. This PR is related to a new REST API endpoint the 1ES team is adding to ADO. Could you kindly review/approve it as soon as possible as we are expecting to ship this quarter. We also need to understand how and when this repository releases. Thanks!

[bhuvanshahMSFT]

@microsoft-github-policy-service agree company="Microsoft"

[bhuvanshahMSFT]

Summary:

• Add optional create args agentPoolName and skipValidation with trimming/omission of empty values.
• Update help for the new flags.
• Add unit tests covering optional fields and trimming.

Tests:

• pytest azext_devops/tests/latest/migration/test_migration.py

Notes:

• Full pytest currently has existing failures in boards/repos auth validation tests (unrelated).

[bhuvanshahMSFT]

Style check fix:

• Resolve flake8 E129 by simplifying the command check in azext_devops/init.py.
• Suppress pylint W0212 for ServiceClient creds access in migration client.
• Exclude local env/venv folders in .flake8 to avoid scanning local environments.

Local: scripts/runStyleCheck.ps1 (pylint OK, flake8 OK).

[bhuvanshahMSFT]

Updates in this push:

• Merge latest master (includes macOS CI fixes).
• Migrations now accept target repositories on github.com and any *.ghe.com host.
• Help YAML fixed (quoted long-summary) to avoid YAML parsing error in �z devops migrations -h.
• Added ELM migrations TSG: doc/elm_migrations_tsg.md.
• Migration tests updated; local run: azext_devops/tests/latest/migration/test_migration.py (12 passed).

[bhuvanshahMSFT]

Added a command reference section to doc/migrations.md to cover the updated migration commands. Commit: 95688f4.

[bhuvanshahMSFT]

Updated BuildWheel task in .vscode/tasks.json to run on Windows by using python from the repo env PATH (fixes path-with-spaces issues). Commit: b51113c.

[bhuvanshahMSFT]

Fixed markdownlint failures by adding blank lines around lists/code blocks in doc/elm_migrations_tsg.md and correcting nested list indentation in doc/migrations.md. Commit: 9d7a0ff.

[v-soujanya]

Hi @bhuvanshahMSFT Can you fix the entire set of lint errors and make sure checks are green?

[v-soujanya]

Hi @bhuvanshahMSFT still there is a failure on lint checks. Could you please take look on this on recent run