refactor(historian): extract Driver.Historian.Sql.Common from the SQL Server backend (no behaviour change) (1a)

Moves the database-independent logic of the SQL Server historian backend into a new
shared library for the upcoming QuestDB backend (#666): status codes and bits, value/column
mapping, StoredSample + quality clamp, the AtTime and aggregate evaluators, BucketPlan,
LiveWritePreparer and HistoryUpdatePlanner (both with a resolutionTicks parameter, default 1),
tag-name rules, the bootstrap failure cache, health counters, alarm event ids, the event
continuation and severity clamp. The SQL Server backend now calls it; its T-SQL, TVP
builders, connection, bootstrapper and catalog stay.

Tests: StatusCodeOracleTests, ValueWriterPrepareTests, the column half of SampleRowMapperTests
and ProcessedReadTests.Every_enum_member_is_either_served_or_refused move to the new
Sql.Common.Tests under the same names. SqlServer integration tests get mechanical renames
only. Test-name set across the three projects is identical to the baseline (160 tests).

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Historian.SqlServer/SqlAggregateQueries.cs

@@ -1,22 +1,10 @@
-using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
+using ZB.MOM.WW.OtOpcUa.Driver.Historian.Sql.Common;
 
 namespace ZB.MOM.WW.OtOpcUa.Driver.Historian.SqlServer;
 
-/// <summary>The SQL shape that serves an aggregate. One query per family.</summary>
-internal enum SqlAggregateFamily
-{
-    /// <summary>Average / Minimum / Maximum / Total / Count / Range / PercentGood / PercentBad: one GROUP BY.</summary>
-    Simple,
-
-    /// <summary>Start / End / Delta: first + last usable sample per bucket (<c>ROW_NUMBER</c>).</summary>
-    StartEnd,
-
-    /// <summary>MinimumActualTime / MaximumActualTime: extreme usable sample per bucket, ties ⇒ earliest.</summary>
-    ActualTime,
-}
-
 /// <summary>
-///     Push-down T-SQL for processed (aggregate) reads (spec §4 "Processed"). Every query takes
+///     Push-down T-SQL for processed (aggregate) reads (spec §4 "Processed"), one query per
+///     <see cref="AggregateFamily"/> (<see cref="AggregateFamilies.FamilyOf"/> picks it). Every query takes
 ///     <c>@id</c> (int TagId), <c>@start</c>/<c>@end</c> (<c>datetime2(7)</c>, the forward window
 ///     <c>[start, end)</c>) and <c>@intervalTicks</c> (bigint bucket width in 100 ns ticks), and returns one row
 ///     per <b>non-empty</b> bucket. The caller generates every interval and fills the empty ones.
@@ -52,19 +40,6 @@ internal static class SqlAggregateQueries
     /// <summary><c>ValueKind</c> of String (4) and DateTime (5): usable but not numeric.</summary>
     private const string NonNumericKinds = "4, 5";
 
-    /// <summary>The family that serves <paramref name="aggregate"/>, or null when this backend does not.</summary>
-    /// <param name="aggregate">Requested aggregate.</param>
-    /// <returns>The family, or null for an unsupported aggregate.</returns>
-    public static SqlAggregateFamily? FamilyOf(HistoryAggregateType aggregate) => aggregate switch
-    {
-        HistoryAggregateType.Average or HistoryAggregateType.Minimum or HistoryAggregateType.Maximum
-            or HistoryAggregateType.Total or HistoryAggregateType.Count or HistoryAggregateType.Range
-            or HistoryAggregateType.PercentGood or HistoryAggregateType.PercentBad => SqlAggregateFamily.Simple,
-        HistoryAggregateType.Start or HistoryAggregateType.End or HistoryAggregateType.Delta => SqlAggregateFamily.StartEnd,
-        HistoryAggregateType.MinimumActualTime or HistoryAggregateType.MaximumActualTime => SqlAggregateFamily.ActualTime,
-        _ => null,
-    };
-
     /// <summary>
     ///     Average / Minimum / Maximum / Total / Count / Range / PercentGood / PercentBad.
     ///     Family columns: <c>6 AvgValue, 7 MinValue, 8 MaxValue, 9 SumValue</c> (float, NULL when no usable