[JAVA] Update JDBC docs

[chernser]

Summary

• Updates type mapping for V2
• Adds explanation of V2 array base type mapping
• Updates migration difference.

Closes: ClickHouse/clickhouse-java#2746
Closes: ClickHouse/clickhouse-java#2606

Checklist

• Delete items not relevant to your PR
• URL changes should add a redirect to the old URL via https://github.com/ClickHouse/clickhouse-docs/blob/main/vercel.json
• If adding a new integration page, also add an entry to the integrations list here: https://github.com/ClickHouse/clickhouse-docs/blob/main/docs/integrations/index.mdx

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Note

Low Risk
Documentation-only changes to the Java JDBC integration page; no runtime or security impact.

Overview
Updates the JDBC V2 documentation in jdbc.mdx so type mapping tables match current driver behavior and migration notes stay accurate.

Type mapping — Replaces many OTHER JDBC codes with standard types (e.g. wide integers and unsigned types → NUMERIC / sized integers, Float32 → FLOAT, enums → VARCHAR, Map → OTHER instead of JAVA_OBJECT). The V1 vs V2 migration tables for numerics and DateTime / DateTime64 are aligned with those codes (including V1 DateTime as TIMESTAMP_WITH_TIMEZONE).

Arrays — Adds an Array Element Type Metadata section describing Array.getBaseTypeName() / getBaseType(), V2 vs V1 signature preservation, nested-array flattening, and example rows for common element types.

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[vercel]

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Project	Deployment	Actions	Updated (UTC)
clickhouse-docs	Ready	Preview, Comment	Jun 1, 2026 4:23pm

4 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
clickhouse-docs-jp	Ignored		Jun 1, 2026 4:23pm
clickhouse-docs-ko	Ignored	Preview	Jun 1, 2026 4:23pm
clickhouse-docs-ru	Ignored	Preview	Jun 1, 2026 4:23pm
clickhouse-docs-zh	Ignored	Preview	Jun 1, 2026 4:23pm

[mintlify]

Docs PR opened: ClickHouse/mintlify-docs-dev#89

Updated the Java JDBC docs with V2 type codes, revised type mappings, and a new Array element metadata section.

Once this PR is merged, we'll do a second pass to capture any additional changes and update the docs PR.