Update servicing branch naming convention for .NET 10+

[Copilot]

Starting with .NET 10, servicing branches no longer use the -staging suffix. Branches are now simply release/10.0, release/11.0, etc., whereas .NET 8 and 9 use release/8.0-staging and release/9.0-staging.

Changes

Commit 1: Backport process documentation and config

• .github/workflows/backport.yml - Updated PR template to document both naming conventions
• docs/project/library-servicing.md - Clarified branch naming varies by version with examples for both patterns

Commit 2: AzDO pipeline configuration

• eng/pipelines/libraries/stress/http.yml - Added release/*.0 pattern alongside release/*-staging
• eng/pipelines/libraries/stress/ssl.yml - Added release/*.0 pattern alongside release/*-staging

All changes maintain backward compatibility with .NET 8 and 9 while supporting the new .NET 10+ convention.

Example backport commands:

# .NET 8/9
/backport to release/9.0-staging

# .NET 10+
/backport to release/10.0

Original prompt

Update the backport template content to revise the instructions for servicing branches. With .NET 8 and .NET 9, we used release/8.0-staging and release/9.0-staging respectively. With .NET 10+, we no longer use the -staging branch name; backports will simply target release/10.0 (or release/X.0 generically).

The backport.yml probably needs to be updated, and the docs/project/library-servicing.md file probably needs updating. There might be azdo pipelines or other configs that referencing the staging branch too--those could be updated as well, but that should be in a separate commit from the servicing backport process docs and config.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/runtime-infrastructure
See info in area-owners.md if you want to be subscribed.

[Copilot]

Pull Request Overview

This PR updates documentation and pipeline configurations to reflect the new branch naming convention for .NET 10+, which drops the -staging suffix from servicing branch names.

• Documents that .NET 10+ servicing branches use release/X.0 format instead of release/X.0-staging
• Updates stress test pipeline schedules to include the new branch pattern
• Updates backport workflow instructions to clarify the different formats

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
eng/pipelines/libraries/stress/ssl.yml	Adds release/*.0 pattern to scheduled branches for .NET 10+
eng/pipelines/libraries/stress/http.yml	Adds release/*.0 pattern to scheduled branches for .NET 10+
docs/project/library-servicing.md	Documents the branch naming convention change and provides examples for both formats
.github/workflows/backport.yml	Updates backport instructions to clarify target branch formats by version

[jeffhandley]

/ba-g Known issues, android timeouts, and infrastructure issues. No code changed in this PR.