fix(historian): SQL quality contract, long-name refusal, info-bit masking, AtTime-after-now, bootstrap hardening

- I-1: an Empty sample is always Bad. The writer stores a non-Bad NaN/Inf as
  Empty+BadOutOfRange and any other non-Bad Empty as BadNoData; the updater
  refuses a non-Bad Empty with BadInvalidArgument; reads clamp a legacy
  non-Bad Empty row to BadNoData (Raw and AtTime).
- Tag/source names over 400 chars are refused, never truncated: writer
  per-tag failure, updater BadInvalidArgument, reads not-found, events none.
- HistorianInfoBits masks the historian bits before setting one.
- AtTime past now, stepped from the last sample => UncertainDataSubNormal.
- Bootstrapper: logger, 5 s negative cache, ClearPool + Warning when
  sp_releaseapplock fails.
- Provider builds its shared state lazily (an invalid Schema no longer
  throws at Resolve); Kinds is a FrozenSet; Gateway reuses the recorder's
  DefaultSupportedKinds.
- Cleanup: SqlHistorianDataTypes in its own file (updater dup removed),
  dead Invalidate and unused status consts deleted, named severity masks,
  alarm writer brace.

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

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Historian.SqlServer.IntegrationTests/AtTimeReadTests.cs

@@ -116,6 +116,19 @@ public sealed class AtTimeReadTests(SqlHistorianFixture fx)
         s.StatusCode.ShouldBe(GoodInterpolated);
     }
 
+    [Fact]
+    public async Task A_time_after_now_stepped_from_the_last_sample_is_uncertain()
+    {
+        var db = await ReadTestDb.CreateAsync(fx);
+        await db.SeedAAsync(); // last sample +40 = 50, Good
+        var src = db.Source(new FixedClock(new DateTimeOffset(At(42))));
+        var s = (await src.ReadAtTimeAsync("A", [At(41), At(45)], Ct)).Samples;
+        s[0].Value.ShouldBe(50d);
+        s[0].StatusCode.ShouldBe(GoodInterpolated);       // after the last sample but not after now: held Good
+        s[1].Value.ShouldBe(50d);
+        s[1].StatusCode.ShouldBe(UncertainInterpolated);  // after now: the value is not known to still hold
+    }
+
     [Fact]
     public async Task An_uncertain_neighbour_makes_the_interpolation_uncertain()
     {