merge release to master

[adamhathcock]

This pull request includes several changes across configuration, build tooling, and the core library, focusing on improving versioning logic, stream handling, and internal diagnostics for 7z archives. The most significant updates are the removal of legacy agent and planning files, enhancements to the build versioning strategy, and improvements to stream management and diagnostics in the core archive code.

Configuration and Documentation Cleanup:

• Removed .copilot-agent.yml and .github/agents/copilot-agent.yml, eliminating old Copilot agent configuration and policies. [1] [2]
• Deleted two detailed planning prompt documents: .github/prompts/plan-async.prompt.md and .github/prompts/plan-for-next.prompt.md, cleaning up project documentation. [1] [2]

Build and Versioning Improvements:

• Enhanced the versioning logic in build/Program.cs to increment the patch version for release branches and the minor version for other branches, with branch detection supporting both local and CI environments. [1] [2] [3]

Core Library Enhancements:

• Refactored stream handling in ArchiveFactory.cs and ArchiveFactory.Async.cs by removing unnecessary wrapping with SharpCompressStream.Create, simplifying stream management for archive operations. [1] [2]
• Updated IArchiveEntryExtensions.cs to use a shared Constants.BufferSize for all copy operations, ensuring consistency and maintainability. [1] [2] [3]
• Changed GZipWritableArchiveEntry.cs to use NonDisposingStream instead of SharpCompressStream.Create for entry streams, improving resource handling.

SevenZip Archive Diagnostics and Internal Improvements:

• Added internal diagnostics support to SevenZipArchive.SevenZipReader, exposing properties for test diagnostics and clarifying folder stream handling for solid archives. Also improved documentation and code comments for maintainability. [1] [2] [3]

API Simplification:

• Simplified IsArchive methods in ArchiveFactory.cs by removing the bufferSize parameter and streamlining overloads.

These changes collectively improve code clarity, maintainability, and diagnostics, while also cleaning up obsolete configuration and documentation files.