chore(bigquery-jdbc): refactor PreparedStatement and CallableStatement (#13849)

* **Centralized Parameter Access & `wasNull()`**: Routed all parameter
getter paths in `BigQueryCallableStatement` through centralized
`getRawParameter` helpers, ensuring consistent `wasNull()` state
tracking across all fast-path and fallback reads.
* **Enforced Lifecycle Validation**: Added `checkClosed()` checks to all
implemented methods in `BigQueryCallableStatement` and
`BigQueryPreparedStatement`.
* **Standardized Logging & Naming**: Aligned method parameter names with
standard JDBC API conventions and added `LOG.finer` entry logging.
* **Handled Unsupported Features**: Updated unsupported getters
(`getRef`, `getSQLXML`) to directly throw
`BigQueryJdbcSqlFeatureNotSupportedException`.
* **Cleaned Redundant Code**: Removed duplicate state-tracking
assignments in calendar-aware date/time/timestamp overloads.

Author: Neenu1995