fix(focas): refuse String on PMC/PARAM/MACRO in the factory, editor and CLI (R07:U8)

FocasDataType.String was authorable on any address, but no area read returns text: PMC
fell through to a byte read, PARAM to Int32, MACRO to a double, and the String node
received a boxed number at Good.

One rule, FocasTagDefinitionFactory.DescribeDataTypeMismatch, now backs every path:
- FromTagConfig rejects the pair, so the driver skips + reports it (BadNodeIdUnknown,
  never a Good number) and Inspect names the reason at deploy;
- FocasTagConfigModel.Validate refuses it on the typed fields;
- the AdminUI editor only offers String where it is readable and shows the rule's text
  inline (kept visible for a loaded blob that already carries it);
- the CLI read/subscribe/probe/write commands refuse it at the boundary.
String stays valid on FIXED: paths (Identity/Program name/mode text) and is ignored on
ALARM: tags; an unparseable address keeps its own diagnosis.

Razor change (FocasTagConfigEditor.razor) needs the Wave 4 live check.

Refs #740
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/Commands/ProbeCommand.cs

@@ -28,6 +28,7 @@ public sealed class ProbeCommand : FocasCommandBase
     {
         ConfigureLogging();
         ValidateOptions();
+        ValidateDataType(Address, DataType);
         var ct = console.RegisterCancellationHandler();
 
         var probeTag = new FocasTagDefinition(

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/Commands/ReadCommand.cs

@@ -19,7 +19,7 @@ public sealed class ReadCommand : FocasCommandBase
 
     /// <summary>Gets the data type to interpret the address as.</summary>
     [CommandOption("type", 't', Description =
-        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16).")]
+        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16). String only on FIXED: paths.")]
     public FocasDataType DataType { get; init; } = FocasDataType.Int16;
 
     /// <inheritdoc />
@@ -28,6 +28,7 @@ public sealed class ReadCommand : FocasCommandBase
         ConfigureLogging();
         // Validate numeric option ranges before any driver work.
         ValidateOptions();
+        ValidateDataType(Address, DataType);
         var ct = console.RegisterCancellationHandler();
 
         var tagName = SynthesiseTagName(Address, DataType);

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/Commands/SubscribeCommand.cs

@@ -18,7 +18,7 @@ public sealed class SubscribeCommand : FocasCommandBase
 
     /// <summary>Gets the data type of the address.</summary>
     [CommandOption("type", 't', Description =
-        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16).")]
+        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16). String only on FIXED: paths.")]
     public FocasDataType DataType { get; init; } = FocasDataType.Int16;
 
     /// <summary>Gets the polling interval in milliseconds.</summary>
@@ -33,6 +33,7 @@ public sealed class SubscribeCommand : FocasCommandBase
         // --interval-ms) before any driver work so a zero/negative interval surfaces as a
         // clean CommandException rather than a tight-spinning poll loop.
         ValidateOptions(IntervalMs);
+        ValidateDataType(Address, DataType);
         var ct = console.RegisterCancellationHandler();
 
         var tagName = ReadCommand.SynthesiseTagName(Address, DataType);

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/Commands/WriteCommand.cs

@@ -20,7 +20,7 @@ public sealed class WriteCommand : FocasCommandBase
 
     /// <summary>Gets the data type of the value to write.</summary>
     [CommandOption("type", 't', Description =
-        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16).")]
+        "Bit / Byte / Int16 / Int32 / Float32 / Float64 / String (default Int16). String only on FIXED: paths.")]
     public FocasDataType DataType { get; init; } = FocasDataType.Int16;
 
     /// <summary>Gets the value to write.</summary>
@@ -37,6 +37,7 @@ public sealed class WriteCommand : FocasCommandBase
         // port/timeout surfaces as a clean CommandException rather than an opaque
         // downstream exception.
         ValidateOptions();
+        ValidateDataType(Address, DataType);
         var ct = console.RegisterCancellationHandler();
 
         var tagName = ReadCommand.SynthesiseTagName(Address, DataType);

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Cli/FocasCommandBase.cs

@@ -89,4 +89,17 @@ public abstract class FocasCommandBase : DriverCommandBase
             throw new CliFx.Exceptions.CommandException(
                 $"--interval-ms must be positive (got {iv}).");
     }
+
+    /// <summary>
+    ///     Refuses an <c>--address</c> / <c>--type</c> pair the driver cannot serve (String on a PMC / PARAM / MACRO
+    ///     address — the driver skips such a tag, so the command would only ever print BadNodeIdUnknown). Same
+    ///     rule as the driver and the AdminUI editor: <see cref="FocasTagDefinitionFactory.DescribeDataTypeMismatch"/>.
+    /// </summary>
+    /// <param name="address">The FOCAS address.</param>
+    /// <param name="type">The data type.</param>
+    protected static void ValidateDataType(string address, FocasDataType type)
+    {
+        if (FocasTagDefinitionFactory.DescribeDataTypeMismatch(type, address) is { } error)
+            throw new CliFx.Exceptions.CommandException(error);
+    }
 }

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.FOCAS.Contracts/FocasTagDefinitionFactory.cs

@@ -53,6 +53,9 @@ public static class FocasTagDefinitionFactory
             // Strict enum read: a typo'd dataType rejects the tag (→ BadNodeIdUnknown)
             // instead of silently defaulting to a wrong-width Good.
             if (!TagConfigJson.TryReadEnumStrict(root, "dataType", FocasDataType.Int32, out var dataType)) return false;
+            // A data type no read of this address can produce (String on PMC / PARAM / MACRO) rejects the tag:
+            // served, it published a boxed number at Good into a String node.
+            if (DescribeDataTypeMismatch(dataType, address) is not null) return false;
             // FOCAS authored tags carry no `writable` key (writability lives on the Tag entity / node ACL):
             // absent ⇒ read-only. An explicit writable:true is honoured for the driver's internal write gate
             // (default-false, so a missing key stays read-only — the note is preserved).
@@ -73,6 +76,26 @@ public static class FocasTagDefinitionFactory
         catch (InvalidOperationException) { return false; }
     }
 
+    /// <summary>
+    ///     The ONE address/data-type compatibility rule, shared by the mapper (and so the driver's init and the
+    ///     deploy inspector), the AdminUI tag editor and the CLI. <see cref="FocasDataType.String"/> is only
+    ///     servable from the fixed tree (Identity / Program name / mode text …): a PMC, parameter or macro read
+    ///     returns a number, which a String node would receive at Good. An <c>ALARM:</c> tag has no value, so its
+    ///     data type is irrelevant; an unparseable address is left to the address check, which names it better.
+    /// </summary>
+    /// <param name="dataType">The authored data type.</param>
+    /// <param name="address">The authored address.</param>
+    /// <returns>The reason the pair cannot be served, or <see langword="null"/> when it can.</returns>
+    public static string? DescribeDataTypeMismatch(FocasDataType dataType, string? address)
+    {
+        if (dataType != FocasDataType.String) return null;
+        var parsed = FocasAddress.TryParse(address);
+        if (parsed is null || parsed.Kind is FocasAreaKind.Fixed or FocasAreaKind.Alarm) return null;
+        return $"FOCAS data type 'String' is not readable at '{address!.Trim()}' — PMC, PARAM: and MACRO: reads " +
+               "return numbers (String is only valid on FIXED: paths such as FIXED:Identity/SeriesNumber). " +
+               "Choose Bit / Byte / Int16 / Int32 / Float32 / Float64.";
+    }
+
     /// <summary>
     ///     The tag's cross-driver <c>alarm</c> object, or <see langword="null"/> when it carries none.
     ///     Lenient like the host's <c>TagConfigIntent</c>: a non-integer <c>severity</c> is simply absent.
@@ -236,6 +259,10 @@ public static class FocasTagDefinitionFactory
         }
 
         if (TagConfigJson.DescribeInvalidEnum<FocasDataType>(root, "dataType") is { } w) rejections.Add(w);
+        else if (addr.ValueKind == JsonValueKind.String
+                 && TagConfigJson.TryReadEnumStrict(root, "dataType", FocasDataType.Int32, out var dataType)
+                 && DescribeDataTypeMismatch(dataType, addr.GetString()) is { } mismatch)
+            rejections.Add(mismatch + " The driver will skip this tag and it will read BadNodeIdUnknown.");
     }
 
     /// <summary>