Enhance verify toolchain

Author: jmh530

.github/workflows/ci.yml

@@ -208,9 +208,22 @@ jobs:
           compiler: ${{ matrix.dc }}
       - name: Verify toolchain
         shell: pwsh
+        env:
+            DC_NAME: ${{ matrix.dc }}
         run: |
-            dmd --version 2>$null; if ($LASTEXITCODE -ne 0) { "dmd not found"; exit 1 }
-            dub --version; if ($LASTEXITCODE -ne 0) { "dub not found"; exit 1 }
+            Write-Host "matrix.dc = $env:DC_NAME"
+            dub --version 2>$null
+            if ($LASTEXITCODE -ne 0) { "dub not found"; exit 1 }
+            
+            if ($env:DC_NAME -like "dmd.*") {
+                dmd --version 2>$null
+                if ($LASTEXITCODE -ne 0) { "dmd not found"; exit 1 }
+            } else if ($env:DC_NAME -like "ldc.*") {
+                ldc2 --version 2>$null
+                if ($LASTEXITCODE -ne 0) { "dmd not found"; exit 1 }
+            } else {
+                throw "Unknown compiler in matrix.dc: '$env:DC_NAME' (expected prefix 'dmd' or 'ldc')"
+            }
             Write-Host "ARCH=$env:ARCH"
             Write-Host "Path=$env:Path"
       - name: Cache dub packages (safe to share)