Fix encoding corruption from #420 and cross-project BlackListManager references

[JusterZhu]

Problem

PR #420 introduced UTF-8 encoding corruption (special characters garbled) and missed cross-project references to the removed \BlackListManager\ singleton.

Changes

1. Restore all files modified in Cleanup: remove deprecated BlackListManager, unify HttpClient via IHttpClientFactory, deduplicate IPC encryption #420 from pre-merge state, re-apply changes with clean encoding
2. Replace \BlackListManager.Instance\ references in:
   • \GeneralUpdate.Differential/Matchers/DefaultDirtyStrategy.cs\
   • \GeneralUpdate.Differential/Pipeline/DiffPipeline.cs\
   • \ ests/CoreTest/Bootstrap/ParameterMatrixAndEventTests.cs\
3. Use \BlackListDefaults\ and \DefaultBlackListMatcher\ instead of removed singleton
4. Fix test assertions to match \DefaultBlackListMatcher\ API