Test Explorer: Debug Test never stops on a breakpoint — no user code is executed

Summary

Set a breakpoint in a test, press Debug Test (the CodeLens above the method, or the Debug profile in the Testing view) against FluentValidation, and nothing happens: no stop, no hit breakpoint, no reported outcome. The run ends without the debuggee ever reaching user code.

Reported against FluentValidation.Tests.AbstractValidatorTester.When_the_Validators_pass_then_the_validatorRunner_should_return_true, breakpoint on the validator.RuleFor(...) line.

Almost certainly the same root cause as #232

A debug run reuses the ordinary run's selection and filter:

• SharpLspTestController.debugTests → collectTests(request) → filterIdsFor(request, tests) (src/editors/vscode/src/testing.ts:506-529)
• those ids are the discovered test ids, which on this project carry xUnit's unique-ID suffix — …When_the_Validators_pass_then_the_validatorRunner_should_return_true (2bd9e5a56e8ea7c7114cb93b1c19bd50a55b7bf4) — see #232 for the on-disk evidence
• filterClause escapes the parentheses, so --filter matches no test

Under VSTEST_HOST_DEBUG=1 the test host still announces its pid and waits, so SharpLsp attaches as designed ([DEBUG-FEATURES-TESTS]) — and then the host runs zero tests and exits. From the user's side that is indistinguishable from "the debugger did nothing": the breakpoint is never reached because the test never runs.

Reproduction

1. Open src/fixtures/real-world/fluentvalidation.
2. Put a breakpoint inside any [Fact] in AbstractValidatorTester.
3. Press Debug Test.
4. No stop; the session ends with no outcome reported.

Expected

The test host runs the selected test under the attached debugger and stops on the user's breakpoint.

What still needs confirming

This issue is filed on the user-reported symptom plus the traced filter defect. Not yet verified from a captured session:

• whether the sharplsp-coreclr attach actually completed (the SharpLsp Test Debug terminal + extension log would say), or whether the attach itself refused
• whether the breakpoint bound (verified) before the host exited

If #232 is fixed and Debug Test still does nothing, this issue stays open on its own merits — so it is tracked separately rather than folded into #232.

Environment

• Windows 11, .NET SDK 10.0.303
• SharpLsp branch fixloading
• FluentValidation.Tests: <TargetFrameworks>net8.0;net9.0</TargetFrameworks>, xunit 2.2.0, xunit.runner.visualstudio 2.2.0

Start in src/editors/vscode/src/testing.ts at SharpLspTestController.debugTests, collectTests(request), and filterIdsFor(request, tests), then reproduce with the FluentValidation fixture and the reported [Fact]. Use VSTEST_HOST_DEBUG=1 plus the SharpLsp Test Debug terminal and extension log to confirm attach and breakpoint binding. Done means the selected test runs under the debugger, reaches the breakpoint, and reports an outcome.