refactor: break up app.js into smaller modules

Split static/js/app.js (581 lines) into 5 focused modules:
- utils.js: global utilities store + legacy compat
- components.js: reusable Alpine.js components (copy, confirm, dismiss, time)
- app-detail.js: app detail page logic (status polling, logs)
- deployment.js: deployment card + deployments history page
- dashboard.js: dashboard relative time updates

Closes #128

templates/base.html

@@ -15,7 +15,11 @@
     </div>
     {{template "footer" .}}
     <script defer src="/s/js/alpine.min.js"></script>
-    <script src="/s/js/app.js"></script>
+    <script src="/s/js/utils.js"></script>
+    <script src="/s/js/components.js"></script>
+    <script src="/s/js/app-detail.js"></script>
+    <script src="/s/js/deployment.js"></script>
+    <script src="/s/js/dashboard.js"></script>
 </body>
 </html>
 {{end}}