Fix event creation denied by private-key rule

The new event creation batched the project doc and its
private/integration API-key doc together. The private-doc create rule
does get(project) (isAdmin), which in a batch evaluates against
pre-commit state where the project doc does not exist yet, so the get
errors and the write is denied (PERMISSION_DENIED at the /private rule).

Write sequentially instead: create the project doc, then the private
key doc. By then get(project) resolves and the owner check passes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: HugoGresse

src/admin/project/core/actions/newProject.js

@@ -49,20 +49,23 @@ export const newProject =
             }
         }
 
-        // Write the project doc and its (member-only) API key atomically. The
-        // key goes in a private subcollection, never on the world-readable
-        // project doc.
+        // Create the project doc first, then its (member-only) API key in a
+        // private subcollection — never on the world-readable project doc. The
+        // writes must be sequential, not batched: the private-doc create rule
+        // does get(project), which in a batch would see the project as
+        // not-yet-created and fail.
         const projectRef = fireStoreMainInstance
             .collection('projects')
             .doc(projectId)
-        const batch = fireStoreMainInstance.batch()
-        batch.set(projectRef, projectData)
-        batch.set(projectRef.collection('private').doc('integration'), {
-            apiKey: generateProjectApiKey(),
-        })
 
-        return await batch
-            .commit()
+        return await projectRef
+            .set(projectData)
+            .then(() =>
+                projectRef
+                    .collection('private')
+                    .doc('integration')
+                    .set({ apiKey: generateProjectApiKey() })
+            )
             .then(() => {
                 dispatch(
                     addNotification({