fix(bundler): properly record if we loaded a "file"

src/bun.js/api/JSBundler.zig

@@ -739,7 +739,7 @@ pub const JSBundler = struct {
                 .value = .pending,
                 .path = parse.path.text,
                 .namespace = parse.path.namespace,
-                .was_file = false,
+                .was_file = parse.path.isFile(),
                 .called_defer = false,
                 .task = undefined,
                 .js_task = undefined,
@@ -1013,7 +1013,7 @@ pub const JSBundler = struct {
             onstart_promises_array: JSC.JSValue,
             is_last: bool,
             is_bake: bool,
-        ) !JSValue {
+        ) bun.JSError!JSValue {
             JSC.markBinding(@src());
             const tracer = bun.tracy.traceNamed(@src(), "JSBundler.addPlugin");
             defer tracer.end();

src/bundler/bundle_v2.zig

@@ -2204,7 +2204,8 @@ pub const BundleV2 = struct {
                 const source = &this.graph.input_files.items(.source)[load.source_index.get()];
                 // If it's a file namespace, we should run it through the parser like normal.
                 // The file could be on disk.
-                if (source.path.isFile()) {
+                if (load.was_file) {
+                    bun.assert(source.path.isFile());
                     this.graph.pool.schedule(load.parse_task);
                     return;
                 }