feat(jdbc): Implement named parameter support in PreparedStatement

[rovshan-b]

Add named bind parameter support (:name syntax)

The Arrow Flight JDBC driver previously only supported positional ? parameters. This PR adds
named parameter support entirely on the client side — no server changes required.

Usage

// Before — positional only
PreparedStatement ps = conn.prepareStatement(
    "SELECT * FROM orders WHERE id = ? AND status = ?");
ps.setInt(1, 42);
ps.setString(2, "active");

// After — named parameters (cast to NamedPreparedStatement to access named setters)
NamedPreparedStatement ps = (NamedPreparedStatement) conn.prepareStatement(
    "SELECT * FROM orders WHERE id = :id AND status = :status");
ps.setInt("id", 42);
ps.setString("status", "active");

// Duplicate name — both slots receive the same value automatically
NamedPreparedStatement ps = (NamedPreparedStatement) conn.prepareStatement(
    "SELECT * FROM events WHERE start_date = :date OR end_date = :date");
ps.setDate("date", someDate);

conn.prepareStatement() always returns a NamedPreparedStatement (which extends
PreparedStatement), so the cast is always safe — regardless of whether the SQL uses named
or positional parameters. This matches the pattern of Oracle's OraclePreparedStatement.
All existing setXxx(int index, …) positional calls continue to work unchanged on the same object.

What's in this PR

File	Change
NamedPreparedStatement.java	New — public interface extending PreparedStatement, declares all named-param setXxx(String, …) methods
NamedParamStatement.java	New (package-private) — NamedPreparedStatement decorator; resolves each name to its 1-based positional index(es) and forwards to the delegate
utils/NamedSqlParser.java	New — single-pass SQL scanner, translates :name → ?, builds name→index maps, rejects mixed ?/:name queries
ArrowFlightConnection.java	Override all prepareStatement(String, …) variants to unconditionally wrap in NamedParamStatement
utils/NamedSqlParserTest.java	11 pure unit tests (string literals, comments, PG casts, mixed-param rejection, etc.)
NamedParamStatementTest.java	6 integration tests against the mock Flight SQL server

Notes

• Translation from :name → ? is client-side only — the server receives a standard positional query unchanged.
• PostgreSQL-style casts (col::int) are correctly left untouched.
• :name tokens inside string literals ('…', "…") and comments (--, /* */) are ignored.
• Mixing ? and :name in the same query throws SQLException.
• Unknown parameter names throw SQLException("Unknown parameter name: '<name>'").
• NamedParamStatement is package-private — callers always program against the NamedPreparedStatement interface.