Vendor Alpine, Flowbite and Datepicker bundles locally

Serve alpinejs 3.15.12, @alpinejs/mask 3.15.12, flowbite 2.4.1 and
flowbite-datepicker 2.0.0 from games/static/js/ instead of jsdelivr, so
pages (and browser tests) work without network access. Adds the
StaticScript primitive for vendored UMD bundles, which cannot be loaded
as ES modules.

https://claude.ai/code/session_01BKurBhE3Qj25p7Bfsg7EeK

common/components/primitives.py

@@ -554,6 +554,12 @@ def ExternalScript(url: str) -> SafeText:
     return mark_safe(f'<script src="{url}"></script>')
 
 
+def StaticScript(filename: str) -> SafeText:
+    """A plain (classic, non-module) `<script src=...>` tag for a static JS
+    file — for vendored UMD bundles, which break inside module scope."""
+    return mark_safe(f'<script src="{static("js/" + filename)}"></script>')
+
+
 def YearPicker(
     year: int | None = None,
     available_years: tuple[int, ...] = (),