feat: add Cloudflare DNS tool suite with multi-instance support

- zone-list, record-list, record-create, record-update, record-delete
- Named instance support (-a flag) with configurable default
- Zone name-to-ID auto-resolution in shared _lib.sh
- Updated credentials loader with cloudflare/cloudflare-<name> services
- TOOLS.md and INFRASTRUCTURE.md guide documentation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tools/cloudflare/record-delete.sh

@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+#
+# record-delete.sh — Delete a DNS record from a Cloudflare zone
+#
+# Usage: record-delete.sh -z <zone> -r <record-id> [-a instance]
+#
+# Options:
+#   -z zone       Zone name or ID (required)
+#   -r record-id  DNS record ID (required)
+#   -a instance   Cloudflare instance name (default: uses credentials default)
+#   -h            Show this help
+set -euo pipefail
+
+MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.config/mosaic}"
+source "$MOSAIC_HOME/tools/_lib/credentials.sh"
+source "$(dirname "$0")/_lib.sh"
+
+ZONE=""
+INSTANCE=""
+RECORD_ID=""
+
+while getopts "z:a:r:h" opt; do
+  case $opt in
+    z) ZONE="$OPTARG" ;;
+    a) INSTANCE="$OPTARG" ;;
+    r) RECORD_ID="$OPTARG" ;;
+    h) head -11 "$0" | grep "^#" | sed 's/^# \?//'; exit 0 ;;
+    *) echo "Usage: $0 -z <zone> -r <record-id> [-a instance]" >&2; exit 1 ;;
+  esac
+done
+
+if [[ -z "$ZONE" || -z "$RECORD_ID" ]]; then
+  echo "Error: -z and -r are both required" >&2
+  exit 1
+fi
+
+cf_load_instance "$INSTANCE"
+ZONE_ID=$(cf_resolve_zone "$ZONE") || exit 1
+
+response=$(curl -s -w "\n%{http_code}" \
+  -X DELETE \
+  -H "Authorization: $(cf_auth)" \
+  -H "Content-Type: application/json" \
+  "${CF_API}/zones/${ZONE_ID}/dns_records/${RECORD_ID}")
+
+http_code=$(echo "$response" | tail -n1)
+body=$(echo "$response" | sed '$d')
+
+if [[ "$http_code" != "200" ]]; then
+  echo "Error: Failed to delete record (HTTP $http_code)" >&2
+  echo "$body" | jq -r '.errors[]?.message // empty' 2>/dev/null >&2
+  exit 1
+fi
+
+echo "Deleted DNS record $RECORD_ID from zone $ZONE"