fix: declare Hive partitioned scans as Range

[gstamatakis95]

Which issue does this PR close?

• Closes Represent Hive/value partitioning without claiming Partitioning::Hash #23436.

Rationale for this change

• Hive grouped scans declare Partitioning::Hash, but no hash ever ran.
• The optimizer treats any two Hash partitionings with equal counts as co-partitioned, so it skips the repartition.
• Partitioned hash joins then drop rows. Fact {A, B, C} joined to dimension {A, C, D} returns only A, because fact group 1 holds B while dimension group 1 holds C.
• Joining a Hive scan to a VALUES list also loses rows, since the planner hash repartitions the other side.

What changes are included in this PR?

• Add FileGroup::group_by_partition_values_with_split_points, returning groups plus the SplitPoints between them.
• Merge values into contiguous chunks rather than round robin. Only contiguous chunks can be described by split points. Group counts are unchanged.
• Add range_partitioning_from_partition_fields and deprecate output_partitioning_from_partition_fields.
• Give ListFilesResult a partition_split_points field and declare Range from ListingTable::scan.
• Declare nothing when split_file_groups_by_statistics re-cuts the groups. Comparing counts misses this, since the re-cut can return the same number.
• Drop the dynamic filter guard in HashJoinExec since itt existed only because Hive groups reported Hash.

What is the testing strategy for this PR?

• TEST 14 and 15 in preserve_file_partitioning.slt cover the two failures above.
• TEST 16 self joins the merged high cardinality table. TEST 17 asserts the statistics re-cut declares nothing.
• Reverting only table.rs makes TEST 14 return one row instead of two and breaks TEST 12.
• Six unit tests route every file through its split points and assert it lands in its own group, covering NULLs, compound keys, a NULL inside a split point, and unordered split points.
• Two datafusion-proto round trips cover Dictionary(UInt16, Utf8) and Utf8View split points.

Are there any user-facing changes?

• EXPLAIN prints Range([col ASC], [(v1), (v2)], N) instead of Hash([col], N).
• Joins between Hive tables with different values gain a RepartitionExec(Range) rather than returning wrong results.
• Partitioned dynamic filter pushdown works again under preserve_file_partitions.
• File group membership changes when distinct values exceed target_partitions. Byte balance can shift on date partitions with larger recent days. Set preserve_file_partitions = 0 to restore the old behaviour.
• API break: ListFilesResult gains a public field. Add partition_split_points: vec![] or use ...
• Providers declaring Hash over value grouped files should move to the new function. They already return missing rows today when the other join input is hash repartitioned.