chore: add the task launcher for the refactor agents

Routes each task to its CLI per MODEL-ROUTING.md (Codex for 01/03/15/16/19,
Gemini for 02/18, MiniMax for the rest), creates the worktree, installs the
toolchain once task 01 has produced a package.json, and runs the agent headless
with permission prompts disabled — these run unattended, and a blocked edit
would just hang.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.agents/scripts/launch.sh

@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+# Launch one refactor task in its own worktree, on the CLI its brief routes it to.
+#
+#   .agents/scripts/launch.sh 01 scaffold
+#   .agents/scripts/launch.sh 02 tokens --base refactor/task-01-scaffold
+#   .agents/scripts/launch.sh 07 primitives --cli mm --fg
+#
+# Routing comes from plans/astro-refactor/MODEL-ROUTING.md. Override with --cli.
+# All three CLIs are launched with their permission prompts disabled: these run
+# unattended inside a worktree, and a blocked edit or bash call just hangs.
+set -euo pipefail
+
+cd "$(git rev-parse --show-toplevel)"
+
+number=${1:?usage: launch.sh <task-number> <slug> [--base ref] [--cli codex|agy|mm] [--fg]}
+slug=${2:?slug, e.g. scaffold}
+shift 2
+
+base="main"
+cli=""
+foreground=0
+while [ $# -gt 0 ]; do
+  case "$1" in
+    --base) base=$2; shift 2 ;;
+    --cli)  cli=$2;  shift 2 ;;
+    --fg)   foreground=1; shift ;;
+    *) echo "unknown flag: $1" >&2; exit 2 ;;
+  esac
+done
+
+# Model routing. Codex takes the long iterate-until-green loops, Gemini the two
+# tasks that need whole-corpus context plus visual judgement, MiniMax the rest.
+if [ -z "$cli" ]; then
+  case "$number" in
+    01|03|15|16|19) cli=codex ;;
+    02|18)          cli=agy   ;;
+    *)              cli=mm    ;;
+  esac
+fi
+
+dir="../af-task-${number}"
+branch="refactor/task-${number}-${slug}"
+plan="plans/astro-refactor/task-${number}-${slug}.md"
+log="$(pwd)/.agents/logs/task-${number}-${slug}.log"
+
+[ -f "$plan" ] || { echo "no plan at $plan — check the number and slug" >&2; exit 1; }
+mkdir -p .agents/logs
+
+# The brief names its own agent; pull it out so the prompt can point at the file.
+agent=$(sed -n 's/.*\*\*Agent\*\*: `\([a-z-]*\)`.*/\1/p' "$plan" | head -1)
+: "${agent:=astro-architect}"
+
+if [ -d "$dir" ]; then
+  echo "worktree $dir already exists — reusing it"
+else
+  git worktree add "$dir" -b "$branch" "$base"
+fi
+
+# npm ci only once task 01 has produced a package.json. Before that there is no
+# toolchain to install, and no hooks to verify.
+if [ -f "$dir/package.json" ]; then
+  ( cd "$dir" && npm ci --prefer-offline && .agents/scripts/verify-hooks.sh )
+fi
+
+prompt=$(cat <<PROMPT
+You are the \`${agent}\` specialist on the ai-for-dummies Astro refactor.
+You are working alone in the git worktree at $(cd "$dir" && pwd), on branch ${branch}.
+
+Read these, in this order, before you write anything:
+
+1. AGENTS.md                       — project entry point and the "never touch" list
+2. .agents/agents/${agent}.md       — your role, what you own, what you must not do
+3. ${plan}                          — your task brief: scope, steps, done-when, do-not
+4. every file the brief and your agent definition tell you to read
+   (.agents/context/*, .agents/rules/*, .agents/skills/*, .agents/checklists/*)
+
+Then do the task. Rules that override your own judgement:
+
+- Stay inside the scope in the brief. Do not do work belonging to another task.
+- Honour every "Do not" line in the brief and in your agent definition.
+- The site must look and read exactly as it does today. This is a refactor,
+  not a redesign. If you find something that looks like a bug in the current
+  design, write it down in the final report — do not fix it.
+- Never delete or weaken an assertion in scripts/verify.mjs to make a suite
+  green. Only the verification-engineer may reduce assertion count, with a
+  written reason per removal.
+- Commit as you go with conventional-commit messages. The commit-msg and
+  pre-commit hooks are live; if a hook rejects you, fix the cause, never
+  bypass with --no-verify.
+- Work through the done-when checklist at the end and actually run each check.
+
+Finish by printing: what you changed, which done-when boxes are genuinely
+ticked, which are not and why, and anything the next task needs to know.
+PROMPT
+)
+
+echo "task    : ${number} ${slug}"
+echo "agent   : ${agent}"
+echo "cli     : ${cli}"
+echo "worktree: ${dir}  (branch ${branch}, from ${base})"
+echo "log     : ${log}"
+echo
+
+run() {
+  case "$cli" in
+    codex)
+      codex exec --dangerously-bypass-approvals-and-sandbox --skip-git-repo-check \
+        -C "$dir" "$prompt"
+      ;;
+    agy)
+      ( cd "$dir" && agy --dangerously-skip-permissions \
+          --model gemini-3.1-pro-high --print-timeout 4h -p "$prompt" )
+      ;;
+    mm)
+      ( cd "$dir" && mm --dangerously-skip-permissions \
+          --model opus -p "$prompt" )
+      ;;
+    *) echo "unknown cli: $cli" >&2; exit 2 ;;
+  esac
+}
+
+if [ "$foreground" = 1 ]; then
+  run 2>&1 | tee "$log"
+else
+  export cli dir prompt
+  nohup bash -c "$(declare -f run); run" >"$log" 2>&1 &
+  echo "launched in background, pid $!"
+  echo "follow: tail -f $log"
+fi

.gitignore

@@ -12,3 +12,6 @@ dist/
 # the per-run captures and diffs are not.
 .agents/snapshots/after/
 .agents/snapshots/diff/
+
+# agent run logs
+.agents/logs/