[nick2781]

Changes

Add independently runnable C++ acceptance tests for the public coroutine-based Redis and MySQL plugins. The tests exercise authentication failures, MySQL TLS trust rejection, server-observed slow commands, client deadlines and explicit recovery through the public connection pools. Independent observer connections establish that slow commands reached the server before deadline assertions; bounded observations reject duplicate or reappearing slow sessions.

The existing basic service cases remain available. Failure scenarios require explicit runner modes and disposable authenticated services; they do not run against an unspecified database or during ordinary offline regression tests.

Validation

At candidate a4dd1aaf, integrated with accepted main 4c068d85:

• Local Redis 7.4.2 and MySQL 8.4.11: both failure modes and existing public-service acceptance passed.
• Both failure modes passed under AddressSanitizer and UndefinedBehaviorSanitizer without diagnostics; leak detection was disabled.
• check-database, TLS-disabled compilation, whole-project clang-format 18 checks, shell syntax and git diff --check passed.
• Disposable services shut down successfully; raw evidence and machine details remain local.

These results cover the listed macOS scenarios. Explicit cancellation, server restart, Redis TLS, shared-library unload and deployment capacity remain separate acceptance work. The Linux GCC run exposed an internal compiler error on braced Redis arguments across coroutine awaits. Materialize owning command objects before awaiting; all assertions remain unchanged. The corrected source passed the listed local and real-service checks; Linux GCC and the complete hosted matrix must still pass before merging.