Replace synchronous Java execution with bounded owned commands. Keep task-scoped readiness observations fresh across later tasks, defer target client prerequisites behind a closeable owner, and join doctor cancellation and cleanup.
Preserve completed physical failures across late cancellation, exact cleanup dependencies and partial observations. Admit target/profile inputs before probing and return typed factory failures instead of unavailable client wrappers.
Validation: 405 focused tests across 24 files, 2 explicit skips; 109 provider/doctor controls rerun after final admission refinement; check:fast and docs:check. Controlled macOS Java-shaped commands and public CLI/MCP workflows; no new JVM/Ghidra or Windows/Linux lifecycle verification.
Measured warm public doctor baseline/candidate: elapsed 0.447/1.223s, CPU 0.624/1.237s, sampled family RSS 379/529MB, reply tokens 3133/3133. Ownership adds cost; no performance improvement claimed. True cold, whole-agent and MCP costs unmeasured.
Refs #4561. Remaining installation file admission tracked in #4672.
