issue: https://github.com/milvus-io/milvus/issues/45691
Add persistent task management for external collections with automatic
detection of external_source and external_spec changes. When source
changes, the system aborts running tasks and creates new ones, ensuring
only one active task per collection. Tasks validate their source on
completion to prevent superseded tasks from committing results.
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Signed-off-by: sunby <sunbingyi1992@gmail.com>
