Add daemon live control foundation

[mamoreau-devolutions]

Summary

• add canonical DbgEng/TTD capability contracts, runtime provenance validation, and serialized per-target DbgEng workers
• expose typed live step-over, deferred symbol breakpoints, breakpoint enablement, and bounded continue-and-wait output capture through MCP and CLI
• document the supported live-control model and add focused contract, request-validation, CLI, and MCP coverage

Validation

• cargo fmt --check
• cargo test -p windbg-dbgeng -p windbg-ttd -p windbg-tool (with _NT_SYMBOL_PATH cleared for isolation)
• cargo build -p windbg-tool

cargo clippy --workspace --all-targets -- -D warnings remains blocked by three pre-existing platform.rs diagnostics: two cloned_ref_to_slice_refs instances and dump_triage_value having eight arguments.