GH-62: Optimize Flight SQL JDBC Statement execution paths

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What Changed

• This change simplifies the Flight SQL JDBC request flow for Statement.executeQuery/executeUpdate avoiding the PreparedStatement request flow
• Preserved the current requirement that Statement.execute(String) still flows through PreparedStatement
  • Right now, Arrow Flight does not offer a good solution for this use case. There is no way for the client to disambiguate between a CommandStatementUpdate or CommandStatemenQuery without doing a server call
• Moved prepared-statement-specific creation and execution concerns into ArrowFlightPreparedStatement
• Similarly, created ArrowFlightStatement with specific logic to handle Statements
• Removed statement/prepared-statement construction details and logic from ArrowFlightMetaImpl. ArrowFlightMetaImpl was left it focused on orchestration

Closes #62.