[ian-pascoe]

Summary

• Bound language-server frame writes with shared absolute operation deadlines.
• Poison incomplete writes and retire the Owner generation, preserving uncertain/unsafe failure semantics.
• Cover request, synchronization, shutdown, and immediate I/O failures with deterministic regressions.
• Complete Plan 011 and record the caller-budget audit.

Closes #46

Verification

• All 136 tests pass, including 3 new transport and 4 new lifecycle regressions.
• Ten lifecycle regression repetitions pass.
• Formatting, Clippy, schema compatibility, stored-state compatibility, and diff checks pass.
• Independent review findings addressed.
• Verified locally on Linux Rust 1.98.1; Windows/macOS/MSRV verification remains for CI.