gRPC-Core Release 1.66.0 and 1.66.1

[AJ Heller]

This is the 1.66.0 (gladiator) release announcement for gRPC-Core and the wrapped languages C++, C#, Objective-C, Python, PHP and Ruby. The latest release notes are here.

Note that the 1.66.1 release is currently for C++ and Python only. It enables EDS dualstack support by default.

Core

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[Python Otel] Manage call tracer life cycle use call arena. (v1.66.x backport). (#37479)
[BoringSSL] Update third_party/boringssl-with-bazel. (#37223)
[Dep] Upgrading Protobuf to v27.2. (#36753)
[Gpr_To_Absl_Logging] Fixing bugs . (#36961)
[chttp2] don't access endpoint in transport ops if it's already been destroyed. (#36921)

C++
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[OTel C++] Fix race when adding and removing callbacks (#37485). (#37508)
[RlsLB] Fix Deadlock (#37459). (#37502)

Python
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[Python Distrib] Change warning to RuntimeError for version incompatibility (v1.66.x backport). (#37477)
Fix issues/36613. (#37022)
[fix] updated invocation_metadata return type hint. (#36894)
[Release] Add warning about PyPi latest version not necessarily matching Github latest version. (#36965)

Ruby
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[ruby] Update google-protobuf dep to allow 3.x and 4.x versions. (#36982)
[ruby] improve the way completion queue pluck operations handle signals and process shutdown. (#36903)