We should have a list to relocate classes in flink-table-planner-blink and flink-table-runtime-blink to avoid class clashes to make both planners available in a lib directory.
Note that, not all the classes can/should be relocated. For examples: calcite classes, PlannerExpressionParserImpl and so on.
The relocation package name is up to discussion. A dedicated path is org.apache.flink.table.blink.