[Pipe] Improve timeout diagnostics and DROP PIPE observability on dev/1.3

[Caideyipi]

Description

Backport #18297 (834418ed5edc62a10c45f5457a7f94a214eac67e) to dev/1.3.

Changes

• Improve timeout-stage diagnostics and report pending DataNodes.
• Introduce PipeStatus.PRE_DELETE and make DROP PIPE persist the pre-delete state before notifying DataNodes and removing ConfigNode metadata.
• Keep drop-procedure serialization backward compatible.
• Prevent heartbeat updates, failure recording, auto-restart, task-agent state changes, and ALTER/START/STOP operations from interfering with a Pipe being dropped.
• Adapt the change to the Java 8 and tree-model-only codebase on dev/1.3; master-only table-model and new i18n infrastructure are intentionally excluded.

Verification

• Spotless and Checkstyle for node-commons and confignode.
• Reactor compile and test-compile for both modules.
• Focused unit tests: PipeMetaDeSerTest, AbstractOperatePipeProcedureV2Test, DropPipeProcedureV2Test, PipeTaskInfoAutoRestartTest, PipeHeartbeatParserTest, PipeTableRespTest, and ConfigPhysicalPlanSerDeTest (97 ConfigNode tests plus PipeMetaDeSerTest).
• git diff --cached --check before commit.

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This PR has:

• been self-reviewed.
• added comments explaining the intent of non-obvious compatibility logic.
• added or updated unit tests to cover new code paths.

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Key changed/added classes (or packages if there are too many classes) in this PR

• AbstractOperatePipeProcedureV2
• DropPipeProcedureV2
• PipeTaskInfo
• PipeHeartbeatParser
• PipeTaskAgent
• PipeStatus