Turbopack: avoid depending on the Project (#78730)

### What?

avoid depending on the Project value directly, since it will change on
every build.

Author: sokra

crates/next-api/src/middleware.rs

@@ -44,7 +44,6 @@ use crate::{
 #[turbo_tasks::value]
 pub struct MiddlewareEndpoint {
     project: ResolvedVc<Project>,
-    build_id: RcStr,
     asset_context: ResolvedVc<Box<dyn AssetContext>>,
     source: ResolvedVc<Box<dyn Source>>,
     app_dir: Option<ResolvedVc<FileSystemPath>>,
@@ -56,15 +55,13 @@ impl MiddlewareEndpoint {
     #[turbo_tasks::function]
     pub fn new(
         project: ResolvedVc<Project>,
-        build_id: RcStr,
         asset_context: ResolvedVc<Box<dyn AssetContext>>,
         source: ResolvedVc<Box<dyn Source>>,
         app_dir: Option<ResolvedVc<FileSystemPath>>,
         ecmascript_client_reference_transition_name: Option<ResolvedVc<RcStr>>,
     ) -> Vc<Self> {
         Self {
             project,
-            build_id,
             asset_context,
             source,
             app_dir,

crates/next-api/src/project.rs

@@ -738,6 +738,11 @@ impl Project {
         *self.mode
     }
 
+    #[turbo_tasks::function]
+    pub(super) async fn is_watch_enabled(&self) -> Result<Vc<bool>> {
+        Ok(Vc::cell(self.watch.enable))
+    }
+
     #[turbo_tasks::function]
     pub(super) async fn per_page_module_graph(&self) -> Result<Vc<bool>> {
         Ok(Vc::cell(*self.mode.await? == NextMode::Development))
@@ -944,7 +949,7 @@ impl Project {
 
             // At this point all modules have been computed and we can get rid of the node.js
             // process pools
-            if self.await?.watch.enable {
+            if *self.is_watch_enabled().await? {
                 turbopack_node::evaluate::scale_down();
             } else {
                 turbopack_node::evaluate::scale_zero();
@@ -1412,7 +1417,6 @@ impl Project {
 
         Ok(Vc::upcast(MiddlewareEndpoint::new(
             self,
-            self.await?.build_id.clone(),
             middleware_asset_context,
             source,
             app_dir.as_deref().copied(),