Add StarRocks connector

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Description

Add an initial native read-only StarRocks connector.

The connector uses the StarRocks JDBC driver for metadata discovery and Apache Arrow Flight SQL for reads. This avoids MySQL-specific metadata assumptions that can break on StarRocks, such as relying on JDBC COLUMN_SIZE being present during type discovery.

The initial version focuses on:

• stable schema, table, view, and column introspection
• DESCRIBE and SHOW CREATE TABLE support
• read-only SELECT queries over Arrow Flight SQL
• predicate, limit, TopN, and basic aggregation pushdown
• Flight SQL partitioned split planning with safe single-split fallback
• optional TLS configuration for Flight SQL connections
• conservative handling of StarRocks-specific and unsigned integer types
• native read support for parseable ARRAY, MAP, and STRUCT values

Out of scope for v1 are writes, schema mutations, connector-managed DDL for complex types, and advanced optimizations beyond Flight SQL partition descriptors returned by StarRocks.

Additional context and related issues

This work follows the design direction discussed in #28735 and is informed by the Doris Flight SQL connector in #29120, while remaining a StarRocks-specific implementation rather than extending the generic MySQL connector path.

Prior StarRocks-specific work for context:

• Add StarRocks connector #17330
• [WIP] Add StarRocks connector #24720

The StarRocks-specific choices in this PR are:

• metadata comes from the StarRocks JDBC driver and StarRocks INFORMATION_SCHEMA rather than MySQL connector metadata code
• reads use Arrow Flight SQL rather than MySQL wire protocol
• catalog-aware metadata supports starrocks.catalog-name, with fallback for StarRocks versions where INFORMATION_SCHEMA.COLUMNS.TABLE_CATALOG is absent or not populated
• Flight SQL can use TLS via connector configuration
• unsupported aggregate forms and non-parseable complex values fall back to Trino execution or conservative type mapping instead of breaking table introspection

Validation includes:

• unit tests for config, type mapping, metadata fallback behavior, Arrow conversion, query building, split planning, and page source behavior
• connector smoke tests following the BaseConnectorSmokeTest pattern
• integration smoke tests against a live StarRocks instance
• local errorprone-compiler validation matching the previously failing CI job

Local validation commands:

• ./mvnw -pl plugin/trino-starrocks test
• ./mvnw -pl plugin/trino-starrocks clean compile test-compile -DskipTests -Dair.check.skip-all=true -P errorprone-compiler
• ./mvnw -pl plugin/trino-starrocks -Dtest=TestStarRocksIntegrationSmokeTest -Dstarrocks.test.integration.enabled=true -Dstarrocks.test.jdbc-url=jdbc:starrocks://127.0.0.1:9031 -Dstarrocks.test.flight-sql-host=127.0.0.1 -Dstarrocks.test.flight-sql-port=9408 test

Local validation notes:

• a Docker-based StarRocks environment was used outside the repository
• the live validation ran against StarRocks 4.0.9-f647589
• FE MySQL was exposed on 9031 and Arrow Flight SQL on 9408
• the gated smoke covered SHOW SCHEMAS, SHOW TABLES, DESCRIBE, SHOW CREATE TABLE, SELECT count(*), datetime reads, views, largeint fallback, and basic aggregation pushdown
• earlier 100k-row local benchmark validation showed representative average latencies of 90.6 ms for SHOW TABLES, 198.6 ms for DESCRIBE, 241.6 ms for SELECT count(*), 252.2 ms for SELECT sum(amount), 253.0 ms for a grouped aggregate, and 261.8 ms for a filtered projection over 1k rows
• these numbers are intended as local validation signals for the native JDBC metadata plus Arrow Flight SQL design, not as a formal performance claim

Release notes

( ) This is not user-visible or is docs only, and no release notes are required.
( ) Release notes are required. Please propose a release note for me.
(x) Release notes are required, with the following suggested text:

## StarRocks connector
* Add the native read-only StarRocks connector backed by StarRocks JDBC metadata and Arrow Flight SQL reads. ({issue}`28735`)

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