fix(ci): define gxt build-time constants in classic-mode vite config

Classic mode pulls in glimmer-next runtime code via @ember/-internals/glimmer
even though the gxt compiler plugin doesn't run. Without inlined values for
WITH_CONTEXT_API / IS_DEV_MODE / etc., the bundled gxt code references them
as free identifiers and crashes at runtime ("ReferenceError: WITH_CONTEXT_API
is not defined"), which globally fails ~3800 tests.

Define the constants for classic mode only; in GXT mode the compiler plugin
inlines them itself and double-replacement could conflict.

Before: 1924/5800 tests passing (33%, 3876 ReferenceError).
After:  5114/9291 tests passing (55%, zero ReferenceError).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

Author: lifeart

vite.config.mjs

@@ -126,6 +126,26 @@ export default defineConfig(({ mode }) => {
         overlay: false,
       },
     },
+    // In classic mode the gxt compiler plugin doesn't run, but glimmer-next
+    // runtime code is still bundled (statically imported by
+    // @ember/-internals/glimmer). That code references build-time constants
+    // (WITH_CONTEXT_API, IS_DEV_MODE, etc.) which would otherwise survive as
+    // free identifiers and crash at runtime. Define them here so the bundled
+    // gxt code behaves correctly. In GXT mode the compiler plugin inlines
+    // these itself, so we omit `define:` to avoid double-replacement.
+    ...(useGxt
+      ? {}
+      : {
+          define: {
+            IS_GLIMMER_COMPAT_MODE: 'true',
+            WITH_EMBER_INTEGRATION: 'true',
+            WITH_HELPER_MANAGER: 'true',
+            WITH_MODIFIER_MANAGER: 'true',
+            WITH_CONTEXT_API: 'true',
+            TRY_CATCH_ERROR_HANDLING: 'false',
+            IS_DEV_MODE: mode === 'development' ? 'true' : 'false',
+          },
+        }),
     build,
     esbuild: false,
     envPrefix: 'VM_',