[#12064] fix(lance): complete V3 type compatibility

[nevzheng]

What changes were proposed in this pull request?

Define and document Lance compatibility for the five Gravitino V3-native type families.

Type family	Outcome
Nanosecond timestamps	Round-trip exact precision-9 timestamps.
Variant	Reject before dataset mutation.
Unknown/Null	Round-trip nullable Unknown through Arrow Null; reject unsupported non-null use.
Geometry	Round-trip through GeoArrow WKB while preserving CRS.
Geography	Round-trip through GeoArrow WKB while preserving CRS and edge-algorithm metadata.

Why are the changes needed?

Lance and Arrow provide exact representations for four families. Variant has no lossless target and must fail without overwriting the existing dataset.

Fix: #12064

Related: #12056

Does this PR introduce any user-facing change?

Yes. Timestamp, nullable Unknown, Geometry, and Geography gain exact mappings, while Variant fails before mutation.

How was this patch tested?

• Added native Lance schema round-trip coverage.
• Verified rejected Variant overwrite leaves the original dataset and metadata intact.
• Covered the Lance-specific module suites and native integration paths.
• Updated docs/lakehouse-generic-lance-table.md.

[github-actions]

Code Coverage Report

Overall Project	67.93% +0.02%	🟢
Files changed	71.05%	🟢

Module	Coverage
aliyun	1.72%	🔴
api	47.82%	🟢
authorization-common	85.96%	🟢
aws	42.04%	🟢
azure	2.47%	🔴
catalog-common	9.92%	🔴
catalog-fileset	80.23%	🟢
catalog-glue	66.91%	🟢
catalog-hive	79.42%	🟢
catalog-jdbc-clickhouse	81.74%	🟢
catalog-jdbc-common	44.22%	🟢
catalog-jdbc-doris	81.6%	🟢
catalog-jdbc-hologres	54.03%	🟢
catalog-jdbc-mysql	79.23%	🟢
catalog-jdbc-oceanbase	80.91%	🟢
catalog-jdbc-postgresql	82.29%	🟢
catalog-jdbc-starrocks	78.51%	🟢
catalog-kafka	77.01%	🟢
catalog-lakehouse-generic	60.45% +3.12%	🟢
catalog-lakehouse-hudi	79.1%	🟢
catalog-lakehouse-iceberg	86.48%	🟢
catalog-lakehouse-paimon	84.25%	🟢
catalog-model	77.72%	🟢
cli	44.5%	🟢
client-java	78.29%	🟢
common	51.95%	🟢
core	82.53%	🟢
filesystem-hadoop3	77.3%	🟢
flink	0.0%	🔴
flink-common	47.09%	🟢
flink-runtime	0.0%	🔴
gcp	14.12%	🔴
hadoop-auth	68.0%	🟢
hadoop-common	12.7%	🔴
hive-metastore-common	53.29%	🟢
iceberg-common	63.63%	🟢
iceberg-rest-server	74.97%	🟢
idp-basic	86.02%	🟢
integration-test-common	0.0%	🔴
jobs	66.17%	🟢
lance-common	25.68% +17.53%	🔴
lance-rest-server	64.84%	🟢
lineage	53.02%	🟢
optimizer	83.24%	🟢
optimizer-api	21.95%	🔴
server	86.1%	🟢
server-common	75.78%	🟢
spark	28.57%	🔴
spark-common	46.01%	🟢
tencent	69.84%	🟢
trino-connector	40.29%	🟢

Files

Module	File	Coverage
catalog-lakehouse-generic	LanceTableOperations.java	62.5%	🟢
lance-common	LanceDataTypeConverter.java	84.86%	🟢