[missymessa]

Summary

Remove the retired Azure DevOps PatGeneratorTool recommendation, command example, and seven-day lifetime statement from docs/Darc.md and the darc authenticate editor guidance.

The generator was retired in dotnet/dnceng#6752. Continue recommending browser/device-code authentication and retain the existing manual PAT alternative, GitHub guidance, settings keys, token handling, and authentication behavior unchanged.

Tracking: AB#12217.

Validation

• Reviewed the complete diff: two files, six deleted guidance lines only.
• scripts/verify.ps1: full build succeeded. Darc tests: 188 passed, one skipped; DarcLib tests: 185 passed.
• The full verifier is not green: 37 Maestro.DataProviders tests and 37 ProductConstructionService.Api tests failed with SQL Server connection errors (server/instance not accessible). No database, test infrastructure, or unrelated application changes are included.
• Changed-file whitespace formatting verification and git diff --check passed.
• dotnet run --project src/Microsoft.DotNet.Darc/Darc --no-build -- --help displayed the actual Darc command list. It returned 1 through the existing parser's non-operation result path.
• A tracked-file search found no remaining PatGenerator or pat-generator references.

No new tests assert fixed help strings; this change removes obsolete guidance without changing authentication logic. Keep this PR in draft for author review. Merge and applicable mirror/VMR propagation remain outstanding; this PR does not close the tracking item by itself.

[Copilot]

🟢 Approval recommended

The guidance-only deletions introduce no blocking issues; the requested draft author-review gate remains separate.

No open issues 🎉

What changed in this PR

Removes retired PAT generator guidance from DARC documentation and authentication editor help without changing authentication behavior.

Changes:

• Deletes the generator recommendation, command example, and seven-day lifetime statement.
• Preserves browser/device-code authentication and manual PAT alternatives.

File	Description
src/​Microsoft.DotNet.Darc/​Darc/​Models/​PopUps/​AuthenticateEditorPopUp.cs	Removes obsolete generator guidance from editor help.
docs/​Darc.md	Removes matching guidance from authentication documentation.

_{Review effort: Balanced}