refactor(bigquery-jdbc): migrate Read Path to BigQueryTypeRegistry

[Neenu1995]

This PR migrates the BigQuery JDBC read-path implementations (Arrow and Json) to utilize the newly introduced BigQueryTypeRegistry for unified type lookups and high-performance coercion.

Also made the following fixes in implementation and tests:

Type Registry Consolidation & Read-Path Migration

• Unified Coercion: Replaced the legacy BigQueryTypeCoercer with BigQueryTypeRegistry as the single source of truth for all type casting and format mapping.
• Result Set Integration: Refactored BigQueryBaseResultSet, BigQueryArrowResultSet, and BigQueryJsonResultSet (along with their nested Struct and Array counterparts) to funnel all getObject() and primitive getter calls through the registry.

Temporal Type & JDBC 4.2 Spec Compliance

• Strict UTC Anchoring: Anchored java.sql.Date to strictly format at UTC midnight, and java.sql.Time to 1970-01-01 in the local JVM, ensuring correct String serialization and civil time preservation.
• Illegal Coercion Blocking: Added explicit guards to throw BigQueryJdbcException for invalid cross-temporal conversions (e.g., blocking java.sql.Date -> java.sql.Time and java.sql.Time -> java.sql.Date), preserving backward compatibility with legacy strictness.
• Formatter Optimization: Extracted DateTimeFormatter compilations into static final constants to guarantee fast-path string serialization for TIMESTAMP (6 decimal precision) and TIME (3 decimal precision) without per-row object allocation penalties.

Complex Types & Boundary Protection

• Arrow Primitives: Handled raw Arrow Integer (days since epoch) and Long (microseconds since epoch) unboxing explicitly inside Arrow structures to bypass global registry mutations, fixing nested RANGE and ARRAY rendering.
• Strict Bounds Checking: Implemented explicit overflow/underflow protections (MAX_VALUE / MIN_VALUE guards) when coercing BigDecimal and Long values down to smaller primitives (Integer, Short, Byte) to prevent silent data corruption.

[gemini-code-assist]

Code Review

This pull request refactors type conversion and mapping across the BigQuery JDBC driver by replacing BigQueryTypeCoercer and BigQueryJdbcTypeMappings with BigQueryTypeRegistry. This change requires several methods to declare throwing SQLException. The review feedback suggests keeping the parameter type as FieldValue in BigQueryJsonStruct to avoid redundant downcasts, catching Exception instead of RuntimeException in BigQueryBaseResultSet to properly handle SQLException during conversion, and removing redundant blank lines in BigQueryTypeRegistry.