test+eng: 37 StructuralInference unit tests; CI reads SDK version from global.json

Task 9 — Testing Improvements:
Add tests/FSharp.Data.Core.Tests/StructuralInference.fs with 37 unit
tests covering the core type-inference module (StructuralInference.fs,
the largest source file at 777 lines) which previously had no dedicated
test file. Tests cover:
- typeTag (all InferedType cases incl. NET6+ DateOnly/TimeOnly)
- subtypeInfered: Top/Null merging, numeric widening hierarchy
  (Bit0+Bit1→Bit, int+int64→int64, int+float→float, decimal+float→float,
   Bit0+bool→bool), incompatible types → Heterogeneous, optionality
- subtypeInfered with Records: field union, different names → Heterogeneous
- inferCollectionType: single type, mixed numeric widening, multiplicity
- getInferedTypeFromString: empty→Null, Bit/bool/int/int64/decimal/string/
  Guid inference, NoInference mode
- InferenceMode'.FromPublicApi: all enum values
- supportsUnitsOfMeasure: numeric vs non-numeric types

All 2957 tests pass (was 2920 before; +37 new).

Task 4 — Engineering Investments:
Replace hardcoded dotnet-version: 10.0.201 in pull-requests.yml (×3)
and push-master.yml (×1) with dotnet-version-file: global.json.
The SDK version is now a single source of truth in global.json
(which already has rollForward: latestMinor). Also update step
names from 'Setup .NET 10' to 'Setup .NET' so they stay accurate
after future SDK bumps.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 2 people

.github/workflows/pull-requests.yml

@@ -13,10 +13,10 @@ jobs:
     timeout-minutes: 10
     steps:
     - uses: actions/checkout@v6
-    - name: Setup .NET 10
+    - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: 10.0.201
+        dotnet-version-file: global.json
     - name: Cache NuGet packages
       uses: actions/cache@v5
       with:
@@ -37,10 +37,10 @@ jobs:
     timeout-minutes: 40
     steps:
     - uses: actions/checkout@v6
-    - name: Setup .NET 10
+    - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: 10.0.201
+        dotnet-version-file: global.json
     - name: Cache NuGet packages
       uses: actions/cache@v5
       with:
@@ -63,10 +63,10 @@ jobs:
     timeout-minutes: 40
     steps:
     - uses: actions/checkout@v6
-    - name: Setup .NET 10
+    - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: 10.0.201
+        dotnet-version-file: global.json
     - name: Cache NuGet packages
       uses: actions/cache@v5
       with:

.github/workflows/push-master.yml

@@ -17,10 +17,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v6
-    - name: Setup .NET 10
+    - name: Setup .NET
       uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: 10.0.201
+        dotnet-version-file: global.json
     - name: Cache NuGet packages
       uses: actions/cache@v5
       with:

tests/FSharp.Data.Core.Tests/FSharp.Data.Core.Tests.fsproj

@@ -44,6 +44,7 @@
     <Compile Include="HtmlAttributeExtensions.fs" />
     <Compile Include="HtmlCssSelectors.fs" />
     <Compile Include="HtmlTableCell.fs" />
+    <Compile Include="StructuralInference.fs" />
     <Compile Include="StructuralTypes.fs" />
     <Compile Include="BaseTypesHtmlDocument.fs" />
     <Compile Include="BaseTypesHtmlGenerics.fs" />