Fix pipe tree database creation on receiver

[Caideyipi]

Supersedes #17986. That PR was accidentally marked as merged while apache/master was force-restored; GitHub does not allow reopening a pull request once it has merged=true.

Description

This PR fixes tree-model pure-data pipe synchronization when the receiver does not already have the source tree database.

For pipe-generated tree inserts and TsFile loads, the receiver may carry an explicit tree database hint such as root.test.sg_0. Partition analysis uses this explicit database name directly, so the normal tree device-path based database auto-creation path is bypassed. As a result, receiver-side writes can repeatedly fail with Create DataPartition failed because the database ... is not exists.

Semantics

Receiver-side tree database creation follows these rules:

• If the sender carries a database and the receiver does not have it, create the database according to the sender-carried database.
• If the sender carries a database and the receiver already has it, do not create it again; ignore the sender-carried database for creation and continue executing the event normally.
• If the sender does not carry a database, meaning it is an old-version event, keep the existing auto-inference behavior and create the database from the statement/device path.
• A database creation conflict is treated the same as success: creation can be attempted unconditionally, and if the receiver reports conflict because the database already exists, the event continues through the normal subsequent flow.

The PR:

• auto-creates explicit tree database hints on the DataNode receiver before executing tree insert/load statements
• recalculates database-level when rebuilding pipe tree load retry statements
• preserves the tree database hint when LoadTsFile fallback conversion replays tablets
• adds a unit test for retry tree load statement database-level reconstruction
• fixes a missing test import exposed by CI

Verification

• mvn -DskipTests spotless:apply -pl iotdb-core/datanode
• git diff --check

mvn -Ddevelocity.off=true compile -pl iotdb-core/datanode was also attempted, but the current workspace fails in unrelated existing datanode/generated sources, e.g. missing Accumulator, IFill, LinearFill, PipeProcessorSubtask#getDisplayTaskID(), and related symbols.