Tracking: LCM+SM runner — reaper, daemon wiring, Runtime/Workspace adapters

[harshitsinghbhandari]

Follow-on to #3 (the LCM + Session Manager lane core, merged via #2). That core is implemented and tested behind fakes; this issue tracks the runner + the adapters we own to get from "tested behind fakes" to a daemon that actually spawns and supervises sessions.

Owner

@harshitsinghbhandari (+ @yyovil on the Agent adapter — a dependency, built separately).

Scope (ours)

Runner / wiring

• Reaper — a periodic timer that (a) samples runtime/process liveness per active session → LCM.ApplyRuntimeObservation, and (b) calls LCM.TickEscalations(now) so duration-based escalations actually fire. (The design assigns the reaper to this lane; the LCM never polls itself.)
• Daemon wiring — replace the main.go stub with the real assembly: construct the LCM + Session Manager with their adapters, start the reaper loop, and handle graceful start/stop/shutdown.
• End-to-end harness — wire LCM + SM + in-memory fakes and prove a full spawn → observe → react → kill flow (integration test), independent of the external lanes.

Carried-forward items (from the core PRs)

• react() out-of-lock dispatch ordering (from feat(lifecycle): ACT layer — reaction table + escalation engine (split B) #6) — reactions fire after the per-session lock releases; give react() a per-session ordering (a small react queue) or re-check the triggering state before dispatch, so concurrent observers can't dispatch on a stale snapshot.
• ExpectedRevision wiring (from feat(lifecycle): LCM Apply* pipeline (split A) #5) — use the LifecyclePatch.ExpectedRevision optimistic-CAS for multi-writer / CDC safety (currently the only guard is the in-process per-session mutex).

Real adapters we own

• Runtime — tmux adapter — Create/Destroy/SendMessage/GetOutput/IsAlive (tmux new-session/has-session/send-keys/capture-pane mechanics).
• Workspace — git-worktree adapter — Create/Destroy/List/Restore, honoring the worktree-remove safety (refuse to rm -rf a path still registered after git worktree prune).

Dependencies (other lanes — coordinate; not blocking the above)

• Agent adapter (claude-code / codex) → @yyovil. The reaper's liveness sampling and the SM's spawn use the Agent port; our work proceeds against the port + a fake until it lands.
• Persistence + CDC (incl. Seed/Get) → Tom.
• SCM poller producing SCMFacts → adil.
• Backend API + OpenAPI → aditi.

Notes

• Everything in Scope (ours) can be built against the existing ports/ interfaces with fakes, then run against real adapters as they land — none of it is blocked on the external lanes.
• Architecture + current status: see docs/ (docs/architecture.md, docs/status.md).