Address review nits: drop redundant ABC base, keep extracted bodies as faithful moves

- TableScan(BaseScan, ABC) -> TableScan(BaseScan): ABC is redundant since
  BaseScan already extends it. No behavioural change (identical MRO,
  ABCMeta metaclass, __abstractmethods__; TableScan stays non-instantiable).
- ManifestGroupPlanner.plan_manifest_entries / plan_files: restore the
  baseline statement order and blank lines so the extracted bodies read as
  verbatim moves of DataScan.scan_plan_helper / _plan_files_local.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: smaheshwar-pltr

pyiceberg/table/__init__.py

@@ -1907,7 +1907,7 @@ def to_polars(self) -> pl.DataFrame:
 S = TypeVar("S", bound="TableScan", covariant=True)
 
 
-class TableScan(BaseScan, ABC):
+class TableScan(BaseScan):
     """A base class for table scans targeting a single snapshot."""
 
     snapshot_id: int | None
@@ -2274,14 +2274,18 @@ def plan_manifest_entries(self, manifests: Iterable[ManifestFile]) -> Iterator[l
         """
         # step 1: filter manifests using partition summaries
         # the filter depends on the partition spec used to write the manifest file, so create a cache of filters for each spec id
+
         manifest_evaluators: dict[int, Callable[[ManifestFile], bool]] = KeyDefaultDict(self._build_manifest_evaluator)
+
         manifests = [
             manifest_file for manifest_file in manifests if manifest_evaluators[manifest_file.partition_spec_id](manifest_file)
         ]
 
         # step 2: filter the data files in each manifest
         # this filter depends on the partition spec used to write the manifest file
+
         partition_evaluators: dict[int, Callable[[DataFile], bool]] = KeyDefaultDict(self._build_partition_evaluator)
+
         min_sequence_number = _min_sequence_number(manifests)
 
         executor = ExecutorFactory.get_or_create()
@@ -2305,11 +2309,11 @@ def plan_files(self, manifests: Iterable[ManifestFile]) -> Iterable[FileScanTask
         Returns:
             List of FileScanTasks that contain both data and delete files.
         """
-        residual_evaluators: dict[int, Callable[[DataFile], ResidualEvaluator]] = KeyDefaultDict(self._build_residual_evaluator)
-
         data_entries: list[ManifestEntry] = []
         delete_index = DeleteFileIndex()
 
+        residual_evaluators: dict[int, Callable[[DataFile], ResidualEvaluator]] = KeyDefaultDict(self._build_residual_evaluator)
+
         for manifest_entry in chain.from_iterable(self.plan_manifest_entries(manifests)):
             data_file = manifest_entry.data_file
             if data_file.content == DataFileContent.DATA: