test(modbus, abcip): align failing integration tests with fixtures

Two real bugs uncovered by re-running with the new fixture defaults
pointing at the shared docker host. Both are test-side, not driver-side.

AbCip — Driver_reads_seeded_DInt_from_ab_server (4 parametrized rows):
  Hardcoded 'ab://127.0.0.1:{port}/1,0' in the deviceUri instead of
  the resolved fixture.Host. The new 10.100.0.35 default (and any
  AB_SERVER_ENDPOINT override) silently couldn't reach this test —
  the driver tried to connect to a non-existent localhost:44818 and
  returned BadCommunicationError on all 4 profile rows. The sibling
  Emulate tests already use the fixture's resolved endpoint; this
  smoke test was missed in the original migration.

  Fix: deviceUri = $"ab://{fixture.Host}:{fixture.Port}/1,0".

Modbus — Float32_With_CDAB_Roundtrips_Through_Wire:
  Test wrote a Float32 to HR 100 (2 consecutive registers: 100+101).
  standard.json's writable HR range declares [100,100] only — a
  single-cell auto-incrementing register, not a 2-register pair. The
  write to register 101 was rejected with Illegal Data Address
  (BadOutOfRange).

  Fix: moved the tag from HR 100 to HR 200 (in standard.json's
  '[200, 209]' scratch range — 10 consecutive writable HRs). The
  Float32+CDAB semantic the test exercises is unchanged.

Modbus — Block_Read_Coalescing_Reduces_PDU_Count_End_To_End:
  Test read HR 300, 302, 304 — outside both the writable ranges and
  the uint16 seed list. pymodbus rejects reads to unseeded HRs even
  though 'hr size' is 2048. BadOutOfRange on every read.

  Fix: moved the tags from 300/302/304 to 200/202/204 (within the
  scratch range). The non-contiguous coalescing semantic (3 tags
  inside a 5-register window with MaxReadGap=5) is preserved.

After this commit:
  - Modbus.IntegrationTests: 6/38 pass / 32 skip / 0 fail
    (was 4 pass / 32 skip / 2 fail; 32 skips are profile-gated
    ExceptionInjectionTests — they need MODBUS_SIM_PROFILE=
    exception_injection and a different container, intentional gating)
  - AbCip.IntegrationTests: 10/12 pass / 2 skip / 0 fail
    (was 6 pass / 2 skip / 4 fail; 2 skips are Emulate tests that
    need the fixture for separate scenarios)

No driver code changed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/AbCipReadSmokeTests.cs

@@ -26,7 +26,11 @@ public sealed class AbCipReadSmokeTests
         await fixture.InitializeAsync();
         try
         {
-            var deviceUri = $"ab://127.0.0.1:{fixture.Port}/1,0";
+            // Use fixture.Host (not hardcoded 127.0.0.1) so the docker-host migration
+            // (10.100.0.35) and AB_SERVER_ENDPOINT overrides reach this test too. The
+            // sibling Emulate tests already use the fixture's resolved endpoint; this
+            // smoke test was missed.
+            var deviceUri = $"ab://{fixture.Host}:{fixture.Port}/1,0";
             var drv = new AbCipDriver(new AbCipDriverOptions
             {
                 Devices = [new AbCipDeviceOptions(deviceUri, profile.Family)],

tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Modbus.IntegrationTests/AddressingGrammarTests.cs

@@ -54,7 +54,12 @@ public sealed class AddressingGrammarTests
     {
         if (_sim.SkipReason is not null) Assert.Skip(_sim.SkipReason);
 
-        var tag = new ModbusTagDefinition("Tank", ModbusRegion.HoldingRegisters, 100, ModbusDataType.Float32,
+        // HR 200 lives in pymodbus's scratch range (`write: [200, 209]` per standard.json),
+        // which gives us two consecutive writable HRs for the Float32 round-trip. The earlier
+        // version used HR 100 — but standard.json declares HR 100 as a single-cell auto-
+        // incrementing register (`write: [100, 100]`) so the second register of the Float32
+        // write was rejected with Illegal Data Address.
+        var tag = new ModbusTagDefinition("Tank", ModbusRegion.HoldingRegisters, 200, ModbusDataType.Float32,
             ByteOrder: ModbusByteOrder.WordSwap);
         var drv = await NewDriverAsync(tag);
 
@@ -87,9 +92,13 @@ public sealed class AddressingGrammarTests
         if (_sim.SkipReason is not null) Assert.Skip(_sim.SkipReason);
 
         // Sanity check that the simulator accepts the larger PDU coalescing produces.
-        var t1 = new ModbusTagDefinition("T1", ModbusRegion.HoldingRegisters, 300, ModbusDataType.Int16);
+        // Using HR 200/202/204 in the scratch range (standard.json's `uint16: 200..209`),
-        var t2 = new ModbusTagDefinition("T2", ModbusRegion.HoldingRegisters, 302, ModbusDataType.Int16);
+        // not 300/302/304 — pymodbus rejects reads outside the seeded uint16 list with
-        var t3 = new ModbusTagDefinition("T3", ModbusRegion.HoldingRegisters, 304, ModbusDataType.Int16);
+        // Illegal Data Address (= BadOutOfRange). The coalescing semantic the test
+        // exercises is identical with the scratch addresses.
+        var t1 = new ModbusTagDefinition("T1", ModbusRegion.HoldingRegisters, 200, ModbusDataType.Int16);
+        var t2 = new ModbusTagDefinition("T2", ModbusRegion.HoldingRegisters, 202, ModbusDataType.Int16);
+        var t3 = new ModbusTagDefinition("T3", ModbusRegion.HoldingRegisters, 204, ModbusDataType.Int16);
         var opts = new ModbusDriverOptions
         {
             Host = _sim.Host, Port = _sim.Port, Tags = [t1, t2, t3], MaxReadGap = 5,