parquet-protobuf: recursion truncation breaks repeated and map fields — ClassCastException in specs-compliant mode, file corruption in the old style

### Describe the bug

`ProtoSchemaConverter` (PARQUET-1711) terminates recursive proto message fields at
`parquet.proto.maxRecursion` depth by replacing them with the serialized proto bytes. The
truncation hardcodes the replacement column as `optional binary`, ignoring the original field's
repetition:

```java
// ProtoSchemaConverter.addMessageField
if (seen.get(typeName).size() > maxRecursion) {
return builder.primitive(BINARY, Type.Repetition.OPTIONAL).as((LogicalTypeAnnotation) null);
}
```

`ProtoWriteSupport.MessageWriter` however still wraps every repeated field's writer in
`ArrayWriter` (specs-compliant) or `RepeatedWriter` (old style), and map fields in `MapWriter` —
all of which emit record structure the `optional binary` column cannot hold. The mock-based unit
tests (`ProtoWriteSupportTest.testRepeatedRecursion` / `testMapRecursion`) never validate against a
real `MessageColumnIO`, so the mismatch was never caught.

Consequences, each reproduced by an end-to-end write test included in the follow-up PR:

1. **Specs-compliant mode, repeated recursive field, data deeper than maxRecursion:** the write
crashes with

```
java.lang.ClassCastException: class org.apache.parquet.io.PrimitiveColumnIO cannot be cast to
class org.apache.parquet.io.GroupColumnIO
```

(`ArrayWriter` calls `startGroup()`/`startField("list", 0)` against a primitive column). This is
a data-dependent landmine: schema creation and shallow rows succeed; the job dies only when a
row's data actually nests past the limit.

2. **Old style (writeSpecsCompliant=false), repeated recursive field with more than one element at
the truncation depth:** no exception — the write emits inconsistent repetition levels for the
second and following elements, **corrupting the file**. Depending on the data, reading it back
either fails with `ParquetDecodingException` (`Can not read value at ... in block`,
EOF/BufferUnderflow underneath) or silently returns a wrong tree (elements lost or attached to
phantom duplicate parent nodes).

3. **Specs-compliant map field at which the recursion budget runs out** (e.g.
`google.protobuf.Struct` maps reached through `list_value` branches): the whole MAP — including
its keys — collapses into a single unreadable binary in the schema, and writing data through
that branch crashes with the same `ClassCastException` (`MapWriter` navigating `key_value`
groups over a primitive column). On map paths where the budget happens to trip at a singular
field first (like `Struct`'s main `fields → struct_value` chain), the schema was already fine —
the collapse is branch-dependent.

### Reproducer

Any repeated self-recursive message nested deeper than maxRecursion, e.g. the existing test proto
`Trees.WideTree`:

```java
Trees.WideTree deep = ...; // chain of children 5 levels deep, 2 children per node
Configuration conf = new Configuration();
ProtoWriteSupport.setWriteSpecsCompliant(conf, true);
ProtoSchemaConverter.setMaxRecursion(conf, 2);
try (ParquetWriter w = ProtoParquetWriter.builder(path)
.withMessage(Trees.WideTree.class).withConf(conf).build()) {
w.write(deep); // ClassCastException
}
```

Affects all released versions since 1.13.0 (PARQUET-1711) through current master (verified on
1.17.1 and master @ e02f65e2).

### Proposed fix (PR follows)

Preserve the field's shape when truncating, mirroring how ordinary repeated primitives are handled:

- `ProtoSchemaConverter.addMessageField`:
- repeated + specs-compliant → LIST-wrapped binary via the existing `addRepeatedPrimitive`
(`optional group x (LIST) { repeated group list { required binary element } }`);
- otherwise `builder.primitive(BINARY, getRepetition(descriptor))` (`repeated binary` in the old
style; truncated optional fields unchanged, proto2 required fields now keep `required`);
- specs-compliant map fields keep their MAP structure unconditionally; a recursive **value** type
is truncated to `optional binary` inside `key_value` when `addMapField` recurses into the value
field (same recursion budget, applied one level deeper where it belongs).
- `ProtoWriteSupport.createMessageWriter`: look through the LIST/MAP wrapper when detecting a
truncated-to-binary message field (`getContentType`, introduced by the fix for #2142, which
terminates empty message types through the same mechanism) so `BinaryWriter` is selected for
truncated elements/values; the existing `ArrayWriter`/`RepeatedWriter`/`MapWriter` wrapping then
lines up with the schema.

With the fix, each repeated element / map value at the truncation depth round-trips as one binary
containing the serialized subtree (`X.parseFrom(bytes)` reconstructs it), keys of truncated-value
maps stay queryable, and truncated optional fields are byte-for-byte unchanged.

Existing expected-schema tests were regenerated (`WideTree.par`, `Value.par`, `Struct.par`,
inline schemas, and the `testDeepRecursion` Struct fan-out series changes from `2n+4` to `2n+5`
because a truncated map now retains its key column). New `ProtoRecursionTruncationTest` (5 tests)
writes through a real `MessageColumnIO`: repeated recursion in both modes, a map field exhausting
the recursion budget (fails with the ClassCastException before the fix), and the already-working
map-main-path and optional cases as regression guards.

Note on schema compatibility: files previously written with a truncated *optional* field are
unchanged. A repeated/map truncated field changes its schema shape — but writing more than one
element at the truncation depth crashed (specs) or corrupted the file (old style) before, so no
valid existing files carry the old shape with meaningful multi-element data.

### Related

- PARQUET-1711 / #995 — introduced maxRecursion truncation (optional-field case only).
- #2708 / PARQUET-2181 — read-side ClassCastException in parquet-cli on proto files; note that
`ProtoParquetReader` itself also cannot read back **any** truncated field (including the optional
case that writes fine): `ProtoMessageConverter.newScalarConverter` has no binary→message path and
throws `ClassCastException` at converter-tree construction. That read-side gap is orthogonal to
this write-side fix and probably deserves its own issue.
- #2142 — empty message types cannot be written at all; the companion PR fixes it with the same
terminate-as-proto-bytes mechanism, and this fix builds on it.

Beginne mit ProtoSchemaConverter.addMessageField und ProtoWriteSupport.createMessageWriter und lies anschließend ProtoWriteSupportTest.testRepeatedRecursion und testMapRecursion. Führe die neuen ProtoRecursionTruncationTest-Fälle über ein echtes MessageColumnIO aus, einschließlich beider Schreibmodi und der Map-Rekursion. Fertig ist die Aufgabe, wenn wiederholte Felder und Map-Werte nicht mehr abstürzen oder die Ausgabe beschädigen und abgeschnittene Werte als serialisierte Bytes den Roundtrip durchlaufen.

Vom Indexierungsmodell aus dem Issue-Text verfasst.