v0.52.0

## What's Changed
* feat: prefix-affinity routing for agentic scaffold reuse by @i386 in https://github.com/michaelneale/mesh-llm/pull/61
* fix: keep HTTP tunnel responses alive after request EOF by @i386 in https://github.com/michaelneale/mesh-llm/pull/59
* fix installer tmpdir cleanup trap by @i386 in https://github.com/michaelneale/mesh-llm/pull/81
* feat(bench): add memory bandwidth benchmark module with per-GPU fingerprinting and gossip propagation by @ndizazzo in https://github.com/michaelneale/mesh-llm/pull/37
* Speed up CI and release builds with sccache and leaner PR jobs by @i386 in https://github.com/michaelneale/mesh-llm/pull/80
* sccache/ccache for faster local builds by @i386 in https://github.com/michaelneale/mesh-llm/pull/83
* Fix blackboard item ID flake by @i386 in https://github.com/michaelneale/mesh-llm/pull/86
* Fix pipeline parallel routing by @i386 in https://github.com/michaelneale/mesh-llm/pull/82
* Hide client VRAM in mesh overview by @i386 in https://github.com/michaelneale/mesh-llm/pull/38
* ci: add split-mode integration test (Host/Worker/Client routing) by @michaelneale in https://github.com/michaelneale/mesh-llm/pull/87
* fix: build-mac.sh breaks on zsh 5.9 (macOS Sequoia) by @michaelneale in https://github.com/michaelneale/mesh-llm/pull/88
* Namespace plugin IPC endpoints per host instance by @i386 in https://github.com/michaelneale/mesh-llm/pull/89
* Normalize HTTP proxy request framing and connection handling by @i386 in https://github.com/michaelneale/mesh-llm/pull/84


**Full Changelog**: https://github.com/michaelneale/mesh-llm/compare/v0.51.0...v0.52.0