Replace CoreCLR DAC bridge with Rust

[mamoreau-devolutions]

Summary

• host the matching CoreCLR DAC in-process through typed Rust COM interfaces
• implement the DbgEng-backed ICLRDataTarget2 callback and retain managed method resolution
• remove the C++ bridge, DLL packaging/staging, and CMake build path

Validation

• cargo fmt --check
• cargo test -p windbg-dbgeng
• cargo clippy --workspace --all-targets
• cargo build -p windbg-tool
• windbg-tool.exe live capabilities --compact

cargo test --workspace was attempted but windbg-install could not start because the existing test executable requires elevation (Win32 error 740).