### What problem does this PR solve?

Issue Number: N/A

Related PR: apache#69886

Problem Summary: When one BE fails, FE can roll back and unregister the query
before a successful BE reports its prepared Paimon files. The late report is
then discarded, leaving uncommitted files behind. This is reproducible with
two BEs by delaying the successful writer's final report.

Make rollback terminal and atomically hand off reported files under the
transaction lock. Retain bounded contexts for recently aborted inserts so
reports received after query removal, or racing with transaction removal,
can still abort their files. Release payload references and perform storage
I/O outside the lock. Never register committing, committed, or unknown-outcome
transactions for late file deletion.

Add fault injection and distributed regression coverage for BE prepare
failure, delayed reports, failure before FE commit, errors after snapshot
publication, and unknown commit outcomes. Process crashes before reporting
files still require orphan-file maintenance.

### Release note

Clean up uncommitted Paimon files when a successful BE reports after another
BE has failed and FE has rolled back the INSERT.

### Check List (For Author)

- Test: Regression test / Unit Test / Manual test
    - 10 Rust BE tests pass under ASAN; 31 focused FE tests pass.
    - Distributed failure suite passes on both FE distribution planners;
      expected output generated by the standard runner and verified normally.
    - Existing Paimon Rust append regression passes.
    - Manual two-BE SIGKILL test confirms failed INSERT publishes no snapshot,
      cleans the healthy writer's files, and succeeds after BE restart.
    - Full ASAN BE/FE build, updated FE build with Checkstyle, and clang-format
      16 preset check pass. Clang-tidy is blocked by existing NOLINTEND and
      local system-header parsing errors.
- Behavior changed: Yes, late reports for aborted Paimon inserts clean files
- Does this need documentation: No, internal failure cleanup

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: A pipeline can finish early or be cancelled before its
sink opens. PaimonTableWriter.close must return the incoming status in
that case, because neither its backend nor its profile has been created.
Guard the whole close path instead of only its final profile update.
Add coverage for successful early completion alongside cancellation.

### Release note

Avoid a Paimon writer crash when a pipeline finishes before opening its sink.

### Check List (For Author)

- Test: Added early-completion unit coverage; clang-format 16 and BE build
  hygiene passed. Native compilation and tests have not been run on master.
- Behavior changed: Yes. Pre-open completion preserves its original status.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: The master plugin transaction manager removes a transaction
before invoking the connector commit. A failure before snapshot publication
therefore cannot rely on the engine's later rollback to clean up acknowledged
BE files. Roll back within the Paimon commit failure path while still PREPARED;
leave COMMITTING/OUTCOME_UNKNOWN files untouched. Test both outcomes with real
prepared data files and verify that subsequent rollback does not abort twice.

Add an exact license-check exclusion for the Rust-generated base64 protocol
fixture, following existing golden-file exclusions; text headers would change
its decoded bytes. Remove an obsolete comment describing FFI as future work.

### Release note

Clean up unpublished Paimon data files when FE fails before attempting commit.

### Check List (For Author)

- Test: FE and Java plugin build with Checkstyle passed. Paimon connector
  904 tests, no failures/errors, one skipped, including the real-file cleanup
  and unknown-outcome tests. clang-format 16, BE build hygiene, shell syntax
  and license YAML validation passed. BE compilation and remaining FE/JNI
  tests are running; native and SQL validation are not claimed as passed.
- Behavior changed: Yes. Pre-publication commit failures clean up immediately;
  uncertain publication outcomes still preserve files.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: Use the existing JNI Thrift serialization helper for the
shared Paimon table descriptor, including its length and exception checks.
Separate Java open arguments and cached Rust table initialization from their
caller functions, and shorten repetitive comments so modified functions meet
clang-tidy complexity and size limits. Apply pointer qualification and
explicit aggregate member initialization reported by clang-tidy.

### Release note

None

### Check List (For Author)

- Test: clang-format 16, BE build hygiene and changed-line clang-tidy passed
  for the affected writer/descriptor/reader paths; JNI source also passed
  full-file clang-tidy. FE/Java build and targeted tests passed before this
  C++ refactor. Final master ASAN BE build is running; native/SQL tests are
  not claimed as passed.
- Behavior changed: No. Reuse existing checked JNI serialization.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: A pipeline can finish early or be cancelled before its
sink opens. PaimonTableWriter.close must return the incoming status in
that case, because neither its backend nor its profile has been created.
Guard the whole close path instead of only its final profile update.
Add coverage for successful early completion alongside cancellation.

### Release note

Avoid a Paimon writer crash when a pipeline finishes before opening its sink.

### Check List (For Author)

- Test: Added early-completion unit coverage; clang-format 16 and BE build
  hygiene passed. Native compilation and tests have not been run on master.
- Behavior changed: Yes. Pre-open completion preserves its original status.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: The master plugin transaction manager removes a transaction
before invoking the connector commit. A failure before snapshot publication
therefore cannot rely on the engine's later rollback to clean up acknowledged
BE files. Roll back within the Paimon commit failure path while still PREPARED;
leave COMMITTING/OUTCOME_UNKNOWN files untouched. Test both outcomes with real
prepared data files and verify that subsequent rollback does not abort twice.

Add an exact license-check exclusion for the Rust-generated base64 protocol
fixture, following existing golden-file exclusions; text headers would change
its decoded bytes. Remove an obsolete comment describing FFI as future work.

### Release note

Clean up unpublished Paimon data files when FE fails before attempting commit.

### Check List (For Author)

- Test: FE and Java plugin build with Checkstyle passed. Paimon connector
  904 tests, no failures/errors, one skipped, including the real-file cleanup
  and unknown-outcome tests. clang-format 16, BE build hygiene, shell syntax
  and license YAML validation passed. BE compilation and remaining FE/JNI
  tests are running; native and SQL validation are not claimed as passed.
- Behavior changed: Yes. Pre-publication commit failures clean up immediately;
  uncertain publication outcomes still preserve files.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: Use the existing JNI Thrift serialization helper for the
shared Paimon table descriptor, including its length and exception checks.
Separate Java open arguments and cached Rust table initialization from their
caller functions, and shorten repetitive comments so modified functions meet
clang-tidy complexity and size limits. Apply pointer qualification and
explicit aggregate member initialization reported by clang-tidy.

### Release note

None

### Check List (For Author)

- Test: clang-format 16, BE build hygiene and changed-line clang-tidy passed
  for the affected writer/descriptor/reader paths; JNI source also passed
  full-file clang-tidy. FE/Java build and targeted tests passed before this
  C++ refactor. Final master ASAN BE build is running; native/SQL tests are
  not claimed as passed.
- Behavior changed: No. Reuse existing checked JNI serialization.
- Does this need documentation: No.

### What problem does this PR solve?

Related PR: apache#69886, apache#70075, apache#69343

Problem Summary: Master now provides paimon-rust v0.5.0-rc1 and Java Paimon
2.1.0. Rebase the writer on master instead of carrying separate dependency
upgrades. Reuse the upstream Java v14 serializer with bounded accumulated
output, remove the v11 and legacy DataFileMeta encoding patch, and regenerate
the real two-writer interop fixture. Reject old protocol requests before
writer admission. Preserve master's vector-search field 42 and use optional
field 43 for the shared descriptor; retain master's SPI additions and bump
the write diagnostics surface to API 30.

The previous BE UT crash was caused by a validation test bypassing init()
and reading an uninitialized scan-params pointer. Explicitly initialize its
missing-descriptor input.

### Release note

Rust Paimon writes use the Java v14 commit protocol matching master's Paimon
2.1.0 SDK and inherit master's paimon-rust dependency version.

### Check List (For Author)

- Test: Third-party build with Rust 1.94.0; real C FFI append, codec bounds,
  version rejection, message ranges and resource release; FE/Java build with
  Checkstyle; Paimon connector 904 tests (one skip); connector SPI 152 tests;
  six Paimon JNI static layout checks; Thrift generation/field audit;
  clang-format 16, header hygiene, shell syntax and whitespace checks.
  JNI Paimon 186 and FE integration 36 tests passed. BE compilation, native tests,
  clang-tidy against the new build and SQL regression are deferred at the
  user's request to leave resources for another PR.
- Behavior changed: Yes; Rust commit messages now use v14 instead of v11.
- Does this need documentation: Yes; existing feature documentation remains
  pending with the draft PR.

### What problem does this PR solve?

Related PR: apache#69886

Problem Summary: The upgraded paimon-rust writer needs native coverage of
credit release, cleanup and the v14 transport. Use the same Parquet buffer
option as the production descriptor instead of the generic write-buffer-size
option, which does not control the Parquet buffer.

Cover empty writes, prepare failure after rolling a file, and sustained
32 MiB dictionary input under a 16 MiB SDK input budget without rolling the
file. Extend the memory-failure case to retry the same batch with a larger
runtime limit. Check complete big-endian frame fields and the metadata
credit retained until report acknowledgement. The exercised paths required
no production logic changes.

### Release note

None

### Check List (For Author)

- Test: ASAN BE compilation and packaging with build.sh; 164 related BE
  tests passed through run-be-ut.sh (20 FFI writer tests, no failures or
  skips); clang-tidy for five modified production translation units and
  the full updated FFI test file; clang-format 16, header hygiene and
  whitespace checks. SQL/distributed regression was not rerun.
- Behavior changed: No; test-only changes.
- Does this need documentation: No; test-only changes.