Feature 01 task 3: Embed the PWA build with SPA fallback (#4)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>
Co-committed-by: dev_agent <dev_agent@cubecraftlabs.com>

internal/server/server.go

@@ -3,20 +3,44 @@ package server
 
 import (
 	"encoding/json"
+	"io/fs"
 	"log/slog"
 	"net/http"
 
 	"github.com/go-chi/chi/v5"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/frontend"
 )
 
+// reservedPrefixes are owned by the API router and are never answered with the
+// SPA's index.html.
+var reservedPrefixes = []string{"/api", "/auth", "/media", "/health"}
+
 // NewRouter returns the HTTP handler for the service. version is reported by
-// GET /health.
-func NewRouter(logger *slog.Logger, version string) http.Handler {
+// GET /health; assets is the web build served for every other GET.
+func NewRouter(logger *slog.Logger, version string, assets fs.FS) (http.Handler, error) {
+	notFound := apiErrorHandler(logger, http.StatusNotFound, "not_found", "not found")
+	methodNotAllowed := apiErrorHandler(logger, http.StatusMethodNotAllowed, "method_not_allowed", "method not allowed")
+
+	web, err := frontend.NewHandler(assets, logger, notFound, reservedPrefixes...)
+	if err != nil {
+		return nil, err
+	}
+
 	r := chi.NewRouter()
+	r.MethodNotAllowed(methodNotAllowed)
+	r.NotFound(notFound)
+
 	r.Get("/health", health(logger, version))
-	r.MethodNotAllowed(apiErrorHandler(logger, http.StatusMethodNotAllowed, "method_not_allowed", "method not allowed"))
-	r.NotFound(apiErrorHandler(logger, http.StatusNotFound, "not_found", "not found"))
-	return r
+	r.Route("/api", func(r chi.Router) {
+		r.MethodNotAllowed(methodNotAllowed)
+		r.NotFound(notFound)
+	})
+	// Catch-all for the PWA. /auth and /media have no routes yet; the frontend
+	// handler passes them to notFound rather than the SPA fallback.
+	r.Method(http.MethodGet, "/*", web)
+	r.Method(http.MethodHead, "/*", web)
+	return r, nil
 }
 
 type errorBody struct {