feat(monitoring): disk metrics via Pushgateway, Loki in Master Overview, Colima move script

- check-disk-space.sh now pushes mac_disk_used_percent + mac_colima_disk_used_gb
  to Pushgateway every hour so vmalert can alert on real macOS disk usage
- alerts.yml: replace broken node-exporter disk alerts with Pushgateway-based ones
- master-overview.json: add "Recent Errors (Loki)" section with live error log
  stream, error rate timeseries and top error sources barchart
- move-colima-to-external-ssd.sh: guided script to move 200GB Colima VM
  datadisk from internal SSD to /Volumes/ManaData (3.6TB external SSD)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/mac-mini/check-disk-space.sh

@@ -58,9 +58,48 @@ send_notification() {
     fi
 }
 
+PUSHGATEWAY_URL="${PUSHGATEWAY_URL:-http://localhost:9091}"
+
+push_disk_metrics() {
+    local disk_label="$1"
+    local mount_point="$2"
+    local usage_pct="$3"
+    local avail_human="$4"
+    local avail_bytes="${5:-0}"
+    local size_bytes="${6:-0}"
+
+    cat <<PROMEOF | curl -s --data-binary @- "${PUSHGATEWAY_URL}/metrics/job/mac_disk/disk/${disk_label}" >/dev/null 2>&1 || true
+# HELP mac_disk_used_percent Disk usage percent on macOS host
+# TYPE mac_disk_used_percent gauge
+mac_disk_used_percent{disk="${disk_label}",mountpoint="${mount_point}",avail_human="${avail_human}"} ${usage_pct}
+# HELP mac_disk_avail_bytes Disk available bytes on macOS host
+# TYPE mac_disk_avail_bytes gauge
+mac_disk_avail_bytes{disk="${disk_label}",mountpoint="${mount_point}"} ${avail_bytes}
+# HELP mac_disk_size_bytes Total disk size bytes on macOS host
+# TYPE mac_disk_size_bytes gauge
+mac_disk_size_bytes{disk="${disk_label}",mountpoint="${mount_point}"} ${size_bytes}
+PROMEOF
+}
+
+push_colima_metrics() {
+    local colima_disk="/Users/mana/.colima/_lima/_disks/colima/datadisk"
+    [ -f "$colima_disk" ] || return 0
+    local used_kb
+    used_kb=$(du -sk "$colima_disk" 2>/dev/null | awk '{print $1}')
+    local used_gb
+    used_gb=$(awk "BEGIN {printf \"%.1f\", ${used_kb:-0} / 1048576}")
+    cat <<PROMEOF | curl -s --data-binary @- "${PUSHGATEWAY_URL}/metrics/job/mac_disk/disk/colima" >/dev/null 2>&1 || true
+# HELP mac_colima_disk_used_gb Colima VM datadisk actual on-disk usage in GB
+# TYPE mac_colima_disk_used_gb gauge
+mac_colima_disk_used_gb ${used_gb}
+PROMEOF
+    log "Colima VM disk: ${used_gb}GB on disk"
+}
+
 check_disk() {
     local mount_point="$1"
     local name="$2"
+    local disk_label="${3:-}"
 
     # Check if mount point exists
     if [ ! -d "$mount_point" ]; then
@@ -77,12 +116,20 @@ check_disk() {
         return 1
     fi
 
-    # Get available space
+    # Get available and total space
     local available
     available=$(df -h "$mount_point" 2>/dev/null | awk 'NR==2 {print $4}')
+    local avail_bytes size_bytes
+    avail_bytes=$(df "$mount_point" 2>/dev/null | awk 'NR==2 {print $4 * 512}')
+    size_bytes=$(df "$mount_point" 2>/dev/null | awk 'NR==2 {print $2 * 512}')
 
     log "$name: ${usage}% used (${available} free)"
 
+    # Push metrics to Pushgateway → Prometheus → vmalert → Telegram
+    if [ -n "$disk_label" ]; then
+        push_disk_metrics "$disk_label" "$mount_point" "$usage" "$available" "${avail_bytes:-0}" "${size_bytes:-0}"
+    fi
+
     # Check thresholds
     if [ "$usage" -ge "$CRITICAL_THRESHOLD" ]; then
         log "CRITICAL: $name at ${usage}%!"
@@ -204,14 +251,17 @@ log "=== ManaCore Disk Space Check ==="
 
 ALERT_STATUS=0
 
-# Check system disk
-check_disk "/" "System Disk" || ALERT_STATUS=$?
+# Check system disk (internal SSD)
+check_disk "/" "System Disk" "internal" || ALERT_STATUS=$?
 
 # Check ManaData volume (external SSD)
 if [ -d "/Volumes/ManaData" ]; then
-    check_disk "/Volumes/ManaData" "ManaData SSD" || ALERT_STATUS=$?
+    check_disk "/Volumes/ManaData" "ManaData SSD" "manaData" || ALERT_STATUS=$?
 fi
 
+# Push Colima VM disk metrics
+push_colima_metrics
+
 # Check Docker disk usage
 check_docker_disk
 

scripts/mac-mini/move-colima-to-external-ssd.sh

@@ -0,0 +1,105 @@
+#!/bin/bash
+# Move Colima VM datadisk from internal SSD to external ManaData SSD
+#
+# The Colima VM datadisk lives at ~/.colima/_lima/_disks/colima/datadisk
+# and can grow to 200GB (sparse). Moving it to the 3.6TB external SSD
+# prevents the internal SSD from filling up and crashing the server.
+#
+# Usage: bash scripts/mac-mini/move-colima-to-external-ssd.sh
+# Run on the Mac Mini server, NOT via Claude Code.
+
+set -e
+export PATH="/usr/local/bin:/opt/homebrew/bin:$PATH"
+
+COLIMA_DISK_SRC="/Users/mana/.colima/_lima/_disks/colima"
+COLIMA_DISK_DST="/Volumes/ManaData/colima-disk"
+LOG="/tmp/move-colima.log"
+
+log() { echo "[$(date '+%H:%M:%S')] $1" | tee -a "$LOG"; }
+
+# Pre-flight checks
+if [ ! -d "/Volumes/ManaData" ]; then
+    echo "ERROR: /Volumes/ManaData not mounted. Plug in the external SSD first."
+    exit 1
+fi
+
+if [ -L "$COLIMA_DISK_SRC" ]; then
+    echo "Colima disk is already a symlink — already moved. Current target:"
+    readlink "$COLIMA_DISK_SRC"
+    exit 0
+fi
+
+AVAIL_GB=$(df -g /Volumes/ManaData 2>/dev/null | awk 'NR==2 {print $4}')
+DISK_GB=$(du -sg "$COLIMA_DISK_SRC" 2>/dev/null | awk '{print $1}')
+log "Colima disk size: ~${DISK_GB}GB  |  ManaData free: ${AVAIL_GB}GB"
+
+if [ "${DISK_GB:-0}" -ge "${AVAIL_GB:-0}" ]; then
+    echo "ERROR: Not enough space on ManaData (need ${DISK_GB}GB, have ${AVAIL_GB}GB)"
+    exit 1
+fi
+
+echo ""
+echo "This will:"
+echo "  1. Stop Colima (all Docker containers will stop)"
+echo "  2. Copy ${COLIMA_DISK_SRC} → ${COLIMA_DISK_DST}"
+echo "  3. Replace original with symlink"
+echo "  4. Restart Colima"
+echo "  5. Restart all Docker containers"
+echo ""
+echo "Estimated copy time: ~5-15 minutes depending on actual disk usage."
+echo ""
+read -p "Continue? (yes/no): " confirm
+[ "$confirm" = "yes" ] || { echo "Aborted."; exit 0; }
+
+# Step 1: Stop Colima
+log "Step 1: Stopping Colima..."
+colima stop 2>&1 | tee -a "$LOG"
+log "Colima stopped."
+
+# Step 2: Copy disk directory to external SSD
+log "Step 2: Copying disk to /Volumes/ManaData/colima-disk ..."
+mkdir -p "$COLIMA_DISK_DST"
+# Use cp -c for APFS clone-copy (fast) or rsync as fallback
+if cp -c -r "$COLIMA_DISK_SRC/." "$COLIMA_DISK_DST/" 2>/dev/null; then
+    log "Copied via APFS clone (fast)."
+else
+    log "APFS clone not available (cross-volume), using rsync..."
+    rsync -ah --progress "$COLIMA_DISK_SRC/" "$COLIMA_DISK_DST/" 2>&1 | tee -a "$LOG"
+fi
+log "Copy complete."
+
+# Step 3: Replace with symlink
+log "Step 3: Replacing original with symlink..."
+mv "$COLIMA_DISK_SRC" "${COLIMA_DISK_SRC}.backup-$(date +%Y%m%d)"
+ln -s "$COLIMA_DISK_DST" "$COLIMA_DISK_SRC"
+log "Symlink created: $COLIMA_DISK_SRC → $COLIMA_DISK_DST"
+
+# Step 4: Start Colima
+log "Step 4: Starting Colima..."
+colima start 2>&1 | tee -a "$LOG"
+log "Colima started."
+
+# Step 5: Wait for Docker, then start containers
+log "Step 5: Starting Docker containers..."
+for i in $(seq 1 12); do
+    docker info >/dev/null 2>&1 && break
+    log "Waiting for Docker... ($i/12)"
+    sleep 5
+done
+
+cd ~/projects/manacore-monorepo
+docker compose -f docker-compose.macmini.yml up -d 2>&1 | tail -5 | tee -a "$LOG"
+log "Containers started."
+
+# Cleanup
+log "Step 6: Verifying symlink..."
+ls -lah "$COLIMA_DISK_SRC"
+df -h /Volumes/ManaData | tail -1
+df -h / | tail -1
+
+echo ""
+echo "Done. Old disk backed up at: ${COLIMA_DISK_SRC}.backup-$(date +%Y%m%d)"
+echo "Once you've verified everything works, delete the backup:"
+echo "  rm -rf ${COLIMA_DISK_SRC}.backup-*"
+echo ""
+echo "Log: $LOG"