Summary

Add full session state serialization and crash recovery to the LoopOrchestrator runtime (#69), replacing the current fragile /tmp file-based status tracking.

Problem / Context

Currently, loop state is tracked via multiple /tmp/ralph-loop-<feature>.* files (status, tokens, phases, baseline, log). If Wiggum crashes or the terminal closes, recovery is limited to what the --resume flag can reconstruct from these temp files.

Competitors have full session persistence with resume that restores complete state, session locking to prevent concurrent runs, and cross-project session registries. As we build the LoopOrchestrator (#69), session persistence should be a first-class concern — not bolted on after.

Roadmap phase: Phase 2 — CONTROL ("Wiggum owns the full process lifecycle")

Proposed Solution

• Persist full orchestrator state to .ralph/sessions/<feature>.json (not /tmp)
• Include: current phase, iteration count, task progress, token usage, git baseline, timestamps, agent config
• Implement session locking (prevent two loops on same feature)
• wiggum resume <feature> restores full state and resumes from exact point of interruption
• Clean up /tmp files on graceful exit; session file persists for crash recovery
• Consider a session registry in ~/.wiggum/sessions.json for cross-project tracking

Files to Modify

Acceptance Criteria

• Loop state persisted to .ralph/sessions/ on every phase transition and iteration boundary
• wiggum resume <feature> restores full state and continues loop
• Session locking prevents concurrent runs on the same feature
• Graceful exit cleans up temp files; session file retained for recovery
• Session survives terminal close, Wiggum crash, and machine reboot