Fix documentation to use --treenode-filter instead of unsupported --filter syntax (#4020)

* Initial plan

* Update docs to use correct --treenode-filter syntax instead of --filter

Co-authored-by: thomhurst <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: thomhurst <[email protected]>

Author: Copilot

docs/docs/advanced/performance-best-practices.md

@@ -482,15 +482,20 @@ public class InMemoryDatabaseTests
 
 ```bash
 # Run fast unit tests first
-dotnet test --filter "Category=Unit" --no-build
+dotnet test --no-build -- --treenode-filter "/*/*/*/*[Category=Unit]"
 
 # Run slower integration tests separately
-dotnet test --filter "Category=Integration" --no-build
+dotnet test --no-build -- --treenode-filter "/*/*/*/*[Category=Integration]"
 
 # Run expensive E2E tests last
-dotnet test --filter "Category=E2E" --no-build
+dotnet test --no-build -- --treenode-filter "/*/*/*/*[Category=E2E]"
 ```
 
+> **Note**: With .NET 10 SDK or newer, you can use the simpler syntax:
+> ```bash
+> dotnet test --no-build --treenode-filter "/**[Category=Unit]"
+> ```
+
 ### Use Test Result Caching
 
 ```xml

docs/docs/examples/tunit-ci-pipeline.md

@@ -331,7 +331,7 @@ test:integration:
     - build
   script:
     - dotnet test --configuration $BUILD_CONFIGURATION --no-build
-      --filter "Category=Integration"
+      -- --treenode-filter "/*/*/*/*[Category=Integration]"
       --report-trx --results-directory ./TestResults
   artifacts:
     when: always
@@ -590,13 +590,18 @@ Run different test categories in separate jobs:
 ```yaml
 # Unit tests (fast)
 - name: Unit Tests
-  run: dotnet test --filter "Category=Unit"
+  run: dotnet test -- --treenode-filter "/*/*/*/*[Category=Unit]"
 
 # Integration tests (slower)
 - name: Integration Tests
-  run: dotnet test --filter "Category=Integration"
+  run: dotnet test -- --treenode-filter "/*/*/*/*[Category=Integration]"
 ```
 
+> **Note**: With .NET 10 SDK or newer, you can use the simpler syntax without the `--` separator:
+> ```yaml
+> run: dotnet test --treenode-filter "/**[Category=Unit]"
+> ```
+
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 Use fail-fast mode for quick feedback in pull requests: