add site to view and upload files

Reviewed-on: sites/file-explorer#4

config/packages/asset_mapper.yaml

@@ -0,0 +1,11 @@
+framework:
+    asset_mapper:
+        # The paths to make available to the asset mapper.
+        paths:
+            - assets/
+        missing_import_mode: strict
+
+when@prod:
+    framework:
+        asset_mapper:
+            missing_import_mode: warn

config/packages/twig.yaml

@@ -0,0 +1,6 @@
+twig:
+    file_name_pattern: '*.twig'
+
+when@test:
+    twig:
+        strict_variables: true

config/packages/web_profiler.yaml

@@ -0,0 +1,17 @@
+when@dev:
+    web_profiler:
+        toolbar: true
+        intercept_redirects: false
+
+    framework:
+        profiler:
+            only_exceptions: false
+            collect_serializer_data: true
+
+when@test:
+    web_profiler:
+        toolbar: false
+        intercept_redirects: false
+
+    framework:
+        profiler: { collect: false }