ci(mq): MQ feeder — enqueue the oldest green PR when the merge queue is empty (PMAT-5843)

docs/roadmaps/entries/PMAT-5843.yaml

@@ -0,0 +1,19 @@
+- id: PMAT-5843
+  github_issue: 5843
+  item_type: task
+  title: 'MQ feeder: every 5 min enqueue the oldest green non-draft PR when the merge queue is empty'
+  status: planned
+  priority: high
+  assigned_to: null
+  created: 2026-10-21T10:55:00Z
+  updated: 2026-10-21T10:55:00Z
+  spec: null
+  acceptance_criteria:
+  - 'scripts/mq_feeder.sh --self-test green; timer live; kicked PRs re-read at 30s and skipped'
+  phases: []
+  subtasks: []
+  estimated_effort: null
+  labels:
+  - kind:code
+  notes: null
+  epic: 5510

docs/roadmaps/entries/PMAT-5846.yaml

@@ -0,0 +1,19 @@
+- id: PMAT-5846
+  github_issue: 5846
+  item_type: task
+  title: 'arm_pr_automerge.sh: stale guard-tree check name (default must be x86-main)'
+  status: planned
+  priority: high
+  assigned_to: null
+  created: 2026-10-21T10:13:29Z
+  updated: 2026-10-21T10:13:29Z
+  spec: null
+  acceptance_criteria:
+  - 'default GUARD_CHECK_NAME names a check run that exists on PR heads; --self-test fixtures updated'
+  phases: []
+  subtasks: []
+  estimated_effort: null
+  labels:
+  - kind:code
+  notes: null
+  epic: 5510

docs/roadmaps/roadmap.yaml

@@ -25359,6 +25359,44 @@ Not done, pending the ruling: moving the 31 fixture files to an obviously synthe
   - kind:code
   notes: null
   epic: 5510
+- id: PMAT-5843
+  github_issue: 5843
+  item_type: task
+  title: 'MQ feeder: every 5 min enqueue the oldest green non-draft PR when the merge queue is empty'
+  status: planned
+  priority: high
+  assigned_to: null
+  created: 2026-10-21T10:55:00Z
+  updated: 2026-10-21T10:55:00Z
+  spec: null
+  acceptance_criteria:
+  - 'scripts/mq_feeder.sh --self-test green; timer live; kicked PRs re-read at 30s and skipped'
+  phases: []
+  subtasks: []
+  estimated_effort: null
+  labels:
+  - kind:code
+  notes: null
+  epic: 5510
+- id: PMAT-5846
+  github_issue: 5846
+  item_type: task
+  title: 'arm_pr_automerge.sh: stale guard-tree check name (default must be x86-main)'
+  status: planned
+  priority: high
+  assigned_to: null
+  created: 2026-10-21T10:13:29Z
+  updated: 2026-10-21T10:13:29Z
+  spec: null
+  acceptance_criteria:
+  - 'default GUARD_CHECK_NAME names a check run that exists on PR heads; --self-test fixtures updated'
+  phases: []
+  subtasks: []
+  estimated_effort: null
+  labels:
+  - kind:code
+  notes: null
+  epic: 5510
 - id: PMAT-5873
   github_issue: 5873
   item_type: task

scripts/mq_feeder_install.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# mq_feeder_install.sh -- PMAT-5843. Install the feeder AND the arm script it calls into the path the user units run
+# (%h/.local/libexec/mq-feeder). The feeder resolves arm_pr_automerge.sh next to itself, so both must be there.
+# Run from a checkout of origin/main; re-run after either script changes (forjar converges the same files on the hosts).
+# Usage: mq_feeder_install.sh [DEST]
+set -euo pipefail
+src="$(cd "$(dirname "$0")" && pwd)"
+dest="${1-$HOME/.local/libexec/mq-feeder}"
+# SEC010 (bashrs): the install target is an argument, so it must be absolute (so an explicit empty arg is refused too) and free of `..`.
+case "$dest" in
+  /*) ;;
+  *) echo "mq_feeder_install: DEST must be an absolute path, got '$dest'" >&2; exit 2 ;;
+esac
+case "/$dest/" in
+  */../*) echo "mq_feeder_install: DEST must not contain '..': $dest" >&2; exit 2 ;;
+esac
+mkdir -p "$dest"
+for s in mq_feeder.sh arm_pr_automerge.sh; do
+  install -m 0755 "$src/$s" "$dest/$s"
+done
+sha256sum "$dest/mq_feeder.sh" "$dest/arm_pr_automerge.sh" > "$dest/INSTALLED.sha256"
+echo "installed to $dest"

scripts/systemd/mq-feeder-summary.service

@@ -0,0 +1,5 @@
+[Unit]
+Description=mq-feeder hourly summary line (PMAT-5843)
+[Service]
+Type=oneshot
+ExecStart=%h/.local/libexec/mq-feeder/mq_feeder.sh --summary

scripts/systemd/mq-feeder-summary.timer

@@ -0,0 +1,6 @@
+[Unit]
+Description=mq-feeder summary at :45
+[Timer]
+OnCalendar=*:45:00
+[Install]
+WantedBy=timers.target

scripts/systemd/mq-feeder.service

@@ -0,0 +1,5 @@
+[Unit]
+Description=mq-feeder: enqueue the oldest green PR when the merge queue is empty (PMAT-5843)
+[Service]
+Type=oneshot
+ExecStart=%h/.local/libexec/mq-feeder/mq_feeder.sh

scripts/systemd/mq-feeder.timer

@@ -0,0 +1,8 @@
+[Unit]
+Description=mq-feeder tick, every 5 min (PMAT-5843)
+[Timer]
+OnBootSec=2min
+OnUnitActiveSec=5min
+AccuracySec=10s
+[Install]
+WantedBy=timers.target