feat(parquet): apply column default values when reading missing fields (2/4)

[huan233usc]

What

Part 2 of 4 of Iceberg v3 column default-value support (POC #731), built on the
schema-layer support merged in #746.

When a column is present in the read (table) schema but absent from a Parquet
data file — because the column was added after those rows were written — fill it
with the column's v3 initial-default instead of null.

Changes

• arrow/literal_util (new): a shared Arrow materializer that converts a
  Literal to an Arrow scalar (ToArrowScalar), to a constant-filled array
  (MakeDefaultArray), or appends it once to a builder
  (AppendDefaultToBuilder). Covers all primitive types, including
  decimal/uuid/fixed and the four timestamp variants.
• Parquet projection (parquet_schema_util.cc): when a field is missing
  from the file and carries an initial-default, project it as
  FieldProjection::Kind::kDefault, mirroring the generic schema_util.cc path
  already merged in feat(schema): represent, serialize and validate v3 column default values (1/4) #746.
• Parquet data (parquet_data_util.cc): materialize the kDefault branch
  via MakeDefaultArray.

Tests

• literal_util_test: scalar/array/builder conversion across primitive types,
  null and narrowing-sentinel handling, and casting to the target Arrow type.
• parquet_data_test: ProjectRecordBatch fills missing required and optional
  default fields, including a nested struct.
• parquet_test: end-to-end — write a file with an old schema, then read it
  through ReaderFactoryRegistry with an evolved schema carrying defaults
  (ReadMissingFieldsWithDefaults).

Stack

1. feat(schema): represent, serialize and validate v3 column default values (1/4) #746 — schema: represent / serialize / validate (merged)
2. this PR — read path: Parquet
3. read path: Avro (follows)
4. schema evolution: addColumn / updateColumnDefault (follows)