test: add E2E smoke test for sync

test_smoke_sync.sh

@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+echo "=== Verstak Sync E2E Smoke Test ==="
+
+SERVER_PORT=18999
+SDIR=$(mktemp -d)
+VD=$(mktemp -d)
+cleanup() { kill "$SPID" 2>/dev/null || true; rm -rf "$SDIR" "$VD"; }
+trap cleanup EXIT
+
+echo ":: Build"
+go build -o /tmp/vs-server ./cmd/verstak-server/
+go build -o /tmp/vs-cli ./cmd/verstak/
+
+echo ":: Start server"
+/tmp/vs-server --port "$SERVER_PORT" --data "$SDIR" --admin-user admin --admin-pass pass > /dev/null 2>&1 &
+SPID=$!
+sleep 2
+
+echo ":: Health"
+curl -sf "http://localhost:$SERVER_PORT/api/v1/health" | grep -q '"ok"' && echo "  OK"
+
+echo ":: Register device"
+REG=$(curl -sf -X POST "http://localhost:$SERVER_PORT/api/v1/device/register" \
+  -H "Content-Type: application/json" -d '{"name":"smoke"}')
+DID=$(echo "$REG" | python3 -c "import sys,json;print(json.load(sys.stdin)['device_id'])")
+AKEY=$(echo "$REG" | python3 -c "import sys,json;print(json.load(sys.stdin)['api_key'])")
+echo "  device=$DID"
+
+echo ":: Init vault"
+/tmp/vs-cli init --vault "$VD"
+
+echo ":: Configure sync"
+cat > "$VD/.verstak/config.yml" <<YML
+sync:
+  server_url: http://localhost:$SERVER_PORT
+  api_key: $AKEY
+  device_id: $DID
+  auto_sync: false
+YML
+
+echo ":: Insert sync op (simulate recorded op)"
+sqlite3 "$VD/.verstak/index.db" \
+  "INSERT INTO sync_ops (id, op_id, device_id, entity_type, entity_id, op_type, payload_json, created_at) VALUES ('e1','e1','$DID','node','n1','create','{\"title\":\"t\"}',datetime('now'));"
+
+echo ":: Push"
+/tmp/vs-cli sync push --vault "$VD" | grep -q "Pushed 1" && echo "  OK"
+
+echo ":: Pull"
+/tmp/vs-cli sync pull --vault "$VD" | grep -q "Pulled" && echo "  OK"
+
+echo ":: Status"
+/tmp/vs-cli sync status --vault "$VD"
+
+echo ""
+echo "=== ALL TESTS PASSED ==="