Make the SerializedDAG & SerializedBaseOp be independent of Task SDK's DAG & BaseOP

[kaxil]

Currently, models.BaseOperator and models.DAG use the Task SDK classes.

This was done to maintain backwards-compat and to get 3.0 in a timely manner.

However, we don't want to depend on Task SDK in the Scheduler or the API-server (airflow-core package) - at least not a required dependency.

We only need to ensure we have enough information for the Scheduler & API-server for a DAG & the Operator. This is done via the SerializedDAG & SerializedBaseOp.

So this task involves: figuring out how we can consolidate: SerializedDAG, models.DAG by not inheriting Task SDK; and same for SerializedBaseOp and models.BaseOperator

To do (not ordered by dependency):

• Timetables
• Assets - Split SDK and serialized asset classes #58993
• DAGNode - Split DAGNode in Core and SDK #59708
• NOTSET and ArgNotSet
• EdgeInfoType Duplicate EdgeInfoType in Core #59774
• DeadlineAlert and related - On hold, tracked in Separate DeadlineAlert implementations in SDK and Core #59303
• BaseOperatorLink
• ExpandInput Clean up SDK references in airflow.models.expandinput #59815
• PriorityWeightStrategy
  • First attempt (reverted) Remove PriorityWeightStrategy reference in SDK #59780
  • Second attempt Re-apply PriorityWeightStrategy SDK work #60112
• Partitions - Going to figure it as we implement them - Tracked in asset partition - core / task SDK separation #59318
• Clean up remaining SDK references in Core Clean up top-level SDK imports in Core #59817
• Remove ti.render_templates()
• Take airflow.serialization.serialized_objects apart
  • SerializedDAG Split serde logic from SerializedDAG #59596
  • SerializedBaseOperator Split SerializedBaseOperator from serde logic #59627
  • XComOperatorLink Move XComOperatorLink to separate module #59776
  • General cleanups
• Move MappedOperator to airflow.serialization.definitions Move MappedOperator to serialization #59628
• Move SchedulerXComArg to airflow.serialization.definitions Move SchedulerXComArg to serialization #59777
• Ensure all things moved have back compat

[uranusjr]

• BaseOperator
• MappedOperator
• DAG