fn-9.17 Run spawning and detach

fn-9.17 Run spawning and detach

Description

Implement ralph spawning and detach behavior for TUI.

File

src/lib/spawn.ts

Functions

// Locate ralph.sh
function findRalphScript(): string | null

// Spawn ralph detached, return run ID
async function spawnRalph(epicId: string): Promise<{runId: string, pid: number}>

// Check if ralph is running for a run
async function isRalphRunning(runId: string): Promise<boolean>

ralph.sh location

Search order:

1. scripts/ralph/ralph.sh (repo-local after /flow-next:ralph-init)
2. plugins/flow-next/skills/flow-next-ralph-init/templates/ralph.sh
3. Error with instructions to run /flow-next:ralph-init

Detach semantics

• Spawn ralph via Bun.spawn with detached: true
• TUI Ctrl+C exits cleanly, ralph keeps running
• Store PID for potential future actions (stop/signal)

Run ID

Ralph creates run ID in format YYYY-MM-DD-NNN. After spawn, poll scripts/ralph/runs/ to detect new run.

Acceptance

• findRalphScript() locates ralph.sh or returns null
• spawnRalph() starts ralph detached
• TUI exit (Ctrl+C) does not kill spawned ralph
• Run ID returned matches new run directory
• Missing ralph.sh shows helpful error message

Done summary

• Added spawn.ts with ralph spawning and detach functionality

• findRalphScript() searches scripts/ralph then plugin template

• spawnRalph() spawns detached, polls for new run ID

• isRalphRunning() checks progress.txt for COMPLETE marker

• Enables TUI to spawn ralph without blocking

• Clean Ctrl+C exit won't kill spawned ralph process

• All tests pass (383 total, 7 new for spawn.ts)

• Lint clean

Evidence

• Commits: 49e181519aafc7d70070cd354bdddbf1f161565b
• Tests: bun test
• PRs: