fix: resolve CC012 None by symbol identity

[georgepwall1991]

Summary

• require .None to resolve to the actual static System.Threading.CancellationToken.None property
• keep default and default(CancellationToken) behavior unchanged
• add a regression guard for a custom token-valued property named None
• prepare release metadata for v1.27.176

Why

CC012 previously matched member syntax by its final identifier only. A custom property named None could carry a canceled or otherwise meaningful token, yet the analyzer and fixer would suggest replacing it with an unrelated in-scope parameter.

Validation

• red-first regression reproduced one unexpected CC012 diagnostic
• focused CC012 tests: 11 passed
• full suite: 630 passed, 0 failed
• Release build: 0 errors (62 intentional sample analyzer warnings)
• touched-file whitespace verification: clean
• package inspection: both analyzer assemblies present; no NuGet dependencies
• self-review completed as requested; no Claude review used

Known repository baseline

The repo-wide style verifier continues to report the existing IDE0011 brace backlog. No new whitespace issue exists in the touched C# files.