feat: harden loose-offline sync for user JWT, schema, and console ops

Enable Binding-scoped agent push/pull, empty-table schema ensure, SyncPage inspect/drop-table, default module import, and agent-bound publish docs from the 宇恒联调意见.

Co-authored-by: Cursor <cursoragent@cursor.com>

platform/internal/dbsync/inspect_test.go

@@ -0,0 +1,34 @@
+package dbsync
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+)
+
+func TestInspectAndPreviewSQLite(t *testing.T) {
+	dir := t.TempDir()
+	dsn := "file:" + filepath.ToSlash(filepath.Join(dir, "inspect.db"))
+	db, err := Open(DriverSQLite, dsn)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := db.Exec(`CREATE TABLE orders (id TEXT PRIMARY KEY, title TEXT); INSERT INTO orders VALUES ('a','one'),('b','two')`); err != nil {
+		_ = db.Close()
+		t.Fatal(err)
+	}
+	_ = db.Close()
+
+	ep := Endpoint{Driver: DriverSQLite, DSN: dsn}
+	ins, err := InspectEndpoint(context.Background(), ep, "remote", false)
+	if err != nil || !ins.OK {
+		t.Fatalf("inspect: %+v %v", ins, err)
+	}
+	if len(ins.Tables) != 1 || ins.Tables[0].Name != "orders" || ins.Tables[0].RowCount != 2 || ins.Tables[0].ColumnCount != 2 {
+		t.Fatalf("tables=%+v", ins.Tables)
+	}
+	prev, err := PreviewTable(context.Background(), ep, "orders", 10)
+	if err != nil || !prev.OK || prev.Total != 2 || len(prev.Rows) != 2 {
+		t.Fatalf("preview: %+v %v", prev, err)
+	}
+}