Fix CSS loading: copy odoo_web.css to frontend, handle /odoo/ static paths

- Copy build/odoo_web.css to frontend/web/static/ so it's served correctly
- Handle /odoo/<addon>/static/ paths in static file handler (strip odoo/ prefix)
- Route /odoo/ paths with /static/ to static handler instead of webclient

All CSS now loads correctly: Bootstrap, FontAwesome, Odoo UI icons, modules.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pkg/server/static.go

@@ -28,6 +28,12 @@ func (s *Server) handleStatic(w http.ResponseWriter, r *http.Request) {
 	}
 
 	path := strings.TrimPrefix(r.URL.Path, "/")
+
+	// Handle /odoo/<addon>/static/<path> → treat as /<addon>/static/<path>
+	if strings.HasPrefix(path, "odoo/") {
+		path = strings.TrimPrefix(path, "odoo/")
+	}
+
 	parts := strings.SplitN(path, "/", 3)
 	if len(parts) < 3 || parts[1] != "static" {
 		http.NotFound(w, r)