refactor: Rename query builder classes for consistency

Standardizes class names for different database query builders, aligning naming conventions across SQLite, MySQL, PostgreSQL implementations, and updating related factory method calls to improve code clarity and maintainability.

TShockAPI/DB/Queries/PostgresQueryBuilder.cs

@@ -0,0 +1,87 @@
+/*
+TShock, a server mod for Terraria
+Copyright (C) 2011-2025 Pryaxis & TShock Contributors
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using MySql.Data.MySqlClient;
+
+namespace TShockAPI.DB.Queries;
+
+/// <summary>
+/// Query Creator for PostgreSQL
+/// </summary>
+public class PostgresQueryBuilder : GenericQueryBuilder
+{
+	/// <inheritdoc />
+	public override string DbTypeToString(MySqlDbType type, int? length) => type switch
+	{
+		MySqlDbType.VarChar when length is not null => "VARCHAR({0})".SFormat(length),
+		MySqlDbType.String when length is not null => "CHAR({0})".SFormat(length),
+		MySqlDbType.Text => "TEXT",
+		MySqlDbType.TinyText => "TEXT",
+		MySqlDbType.MediumText => "TEXT",
+		MySqlDbType.LongText => "TEXT",
+		MySqlDbType.Float => "REAL",
+		MySqlDbType.Double => "DOUBLE PRECISION",
+		MySqlDbType.Int32 => "INT",
+		MySqlDbType.Int64 => "BIGINT",
+		MySqlDbType.DateTime => "TIMESTAMP",
+
+		_ => throw new NotImplementedException(Enum.GetName(typeof(MySqlDbType), type))
+	};
+
+	/// <inheritdoc />
+	protected override string EscapeTableName(string table) => table.SFormat("\"{0}\"", table);
+
+	/// <inheritdoc />
+	public override string CreateTable(SqlTable table)
+	{
+		ValidateSqlColumnType(table.Columns);
+
+		IEnumerable<string> columns = table.Columns.Select(c =>
+		{
+			// Handle PostgreSQL-specific auto-increment using SERIAL/BIGSERIAL
+			string dataType;
+
+			if (c.AutoIncrement)
+			{
+				dataType = c.Type is MySqlDbType.Int32 ? "SERIAL" : "BIGSERIAL";
+			}
+			else
+			{
+				dataType = DbTypeToString(c.Type, c.Length);
+			}
+
+			return "{0} {1} {2} {3} {4}".SFormat(c.Name,
+				dataType,
+				c.Primary ? "PRIMARY KEY" : "",
+				c.NotNull && !c.AutoIncrement ? "NOT NULL" : "", // SERIAL implies NOT NULL
+				c.DefaultCurrentTimestamp ? "DEFAULT CURRENT_TIMESTAMP" : "");
+		});
+
+		string[] uniques = table.Columns
+			.Where(c => c.Unique).Select(c => c.Name)
+			.ToArray(); // No re-enumeration
+
+		return $"CREATE TABLE {EscapeTableName(table.Name)} ({string.Join(", ", columns)} {(uniques.Any() ? ", UNIQUE({0})".SFormat(string.Join(", ", uniques)) : "")})";
+	}
+
+	/// <inheritdoc />
+	public override string RenameTable(string from, string to) => "ALTER TABLE {0} RENAME TO {1}".SFormat(from, to);
+}