fix(@angular/build): pass process environment variables to prerender workers

Worker processes used for prerendering and route extraction now inherit `process.env`. This ensures that any custom environment variables required
by the application are available during the server-side rendering process.

Closes #32730

Author: alan-agius4

packages/angular/build/src/utils/server-rendering/prerender.ts

@@ -227,6 +227,7 @@ async function renderPages(
     execArgv: workerExecArgv,
     env: {
       'NG_ALLOWED_HOSTS': 'localhost',
+      ...process.env,
     },
   });
 
@@ -342,6 +343,7 @@ async function getAllRoutes(
     execArgv: workerExecArgv,
     env: {
       'NG_ALLOWED_HOSTS': 'localhost',
+      ...process.env,
     },
   });