Stub out migration guides

apps/reference/docs/guides/migrations/firebase-auth.mdx

@@ -0,0 +1,7 @@
+---
+id: firebase-auth
+title: 'Firebase Auth Migration'
+description: 'Migrate Firebase auth users to a Supabase project.'
+sidebar_label: Firebase Auth
+---
+

apps/reference/docs/guides/migrations/firebase-storage.mdx

@@ -0,0 +1,7 @@
+---
+id: firebase-storage
+title: 'Firebase Storage Migration'
+description: 'Migrate Firebase Storage files to Supabase Storage.'
+sidebar_label: Firebase Storage
+---
+

apps/reference/docs/guides/migrations/firestore-data.mdx

@@ -0,0 +1,7 @@
+---
+id: firestore-data
+title: 'Firestore Data Migration'
+description: 'Migrate your Firebase Firestore database to a Supabase Postgres database.'
+sidebar_label: Firestore Data
+---
+

apps/reference/docs/guides/migrations/heroku.mdx

@@ -0,0 +1,8 @@
+---
+id: heroku
+title: 'Migrate from Heroku to Supabase'
+description: 'Migrate your Heroku Postgres database to Supabase.'
+sidebar_label: Heroku
+---
+
+

apps/reference/nav/_referenceSidebars.js

@@ -3,13 +3,13 @@ const sidebars = {
     {
       type: 'category',
       label: 'Overview',
+      collapsed: true,
       items: [
         'about',
         'architecture',
         'guides/hosting/platform',
         'guides/examples',
       ],
-      collapsed: true,
     },
     {
       type: 'category',
@@ -32,6 +32,17 @@ const sidebars = {
         'guides/with-vue-3',
       ],
     },
+    {
+      type: 'category',
+      label: 'Migrate to Supabase',
+      collapsed: true,
+      items: [
+        'guides/migrations/firebase-auth',
+        'guides/migrations/firestore-data',
+        'guides/migrations/firebase-storage',
+        'guides/migrations/heroku',
+      ],
+    },    
     {
       type: 'category',
       label: 'Supabase CLI',