Move rendering into private templates

Add an explicit template renderer with HTML views and partials for the app, bootstrap, package, and catalog pages. Move shared reporting setup into config/reporting.php and relocate stylesheet assets under css/.

private/viewdata.php

@@ -0,0 +1,11 @@
+<?php
+/*
+ * Helpers for reading non-rendered data from view templates.
+ */
+
+require_once __DIR__ . '/Template.php';
+
+function seed_template_translations($languageStore, $template)
+{
+    $languageStore->seedDefaults(RacketSandboxTemplate::translationsFile($template));
+}