Minimalist UI: hide all elements until activated; add help modal and keyboard shortcuts

- Redesign UI to be invisible by default: only header + '?' button shown
- Press m to show sidebar, t for toolbar, / for search, ? for help
- Add help modal with all keyboard shortcuts
- Fix scanner to skip corrupt/unprobeable files instead of aborting
- Fix scanner to skip thumbnail errors instead of aborting
- Fix rescan to use background context so it completes after HTTP response
- Rename project from KISS Media Player to Player

1 files changed, 15 insertions, 0 deletions

diff --git a/internal/api/middleware.go b/internal/api/middleware.go
index ee1d6c9..fd779b5 100644
--- a/internal/api/middleware.go
+++ b/internal/api/middleware.go
@@ -29,15 +29,24 @@ func NewMiddleware(store repository.Store, sm *auth.SessionManager) *Middleware
 }
 
 // RequireSession validates the session cookie and injects the session into request context.
+// For HTML page requests (Accept: text/html), redirects to /login.html instead of returning 401.
 func (mw *Middleware) RequireSession(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		cookie, err := r.Cookie("session")
 		if err != nil {
+			if wantsHTML(r) {
+				http.Redirect(w, r, "/login.html", http.StatusTemporaryRedirect)
+				return
+			}
 			http.Error(w, "unauthorized", http.StatusUnauthorized)
 			return
 		}
 		sess, err := mw.sm.ValidateSession(r.Context(), cookie.Value)
 		if err != nil || sess == nil {
+			if wantsHTML(r) {
+				http.Redirect(w, r, "/login.html", http.StatusTemporaryRedirect)
+				return
+			}
 			http.Error(w, "unauthorized", http.StatusUnauthorized)
 			return
 		}
@@ -46,6 +55,12 @@ func (mw *Middleware) RequireSession(next http.Handler) http.Handler {
 	})
 }
 
+// wantsHTML returns true if the request appears to be from a browser expecting an HTML page.
+func wantsHTML(r *http.Request) bool {
+	accept := r.Header.Get("Accept")
+	return strings.Contains(accept, "text/html")
+}
+
 // RequireAdmin ensures the authenticated user is an admin.
 func (mw *Middleware) RequireAdmin(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {