feat: add standalone task detail page for Android widget deep-links

Adds GET /task?id=xxx&source=xxx route that renders a full mobile-friendly
task detail page (session-protected). Widget task rows now open this page
when tapped. HandleUpdateTask redirects back to the page after a non-HTMX
save. Android: threads serverUrl through composable chain to TaskRow.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 57 insertions, 1 deletions

diff --git a/internal/handlers/handlers.go b/internal/handlers/handlers.go
index 19d26be..0903cf3 100644
--- a/internal/handlers/handlers.go
+++ b/internal/handlers/handlers.go
@@ -814,6 +814,58 @@ func (h *Handler) HandleGetTaskDetail(w http.ResponseWriter, r *http.Request) {
 	}{title, id, source, description})
 }
 
+// HandleTaskDetailPage renders a standalone full-page task detail view (used by Android widget deep-links).
+func (h *Handler) HandleTaskDetailPage(w http.ResponseWriter, r *http.Request) {
+	id := r.URL.Query().Get("id")
+	source := r.URL.Query().Get("source")
+
+	if id == "" || source == "" {
+		http.Error(w, "Missing id or source", http.StatusBadRequest)
+		return
+	}
+
+	var title, description string
+	switch source {
+	case "todoist":
+		if tasks, err := h.store.GetTasks(); err == nil {
+			for _, t := range tasks {
+				if t.ID == id {
+					title, description = t.Content, t.Description
+					break
+				}
+			}
+		}
+	case "trello":
+		if boards, err := h.store.GetBoards(); err == nil {
+			for _, b := range boards {
+				for _, c := range b.Cards {
+					if c.ID == id {
+						title = c.Name
+						break
+					}
+				}
+			}
+		}
+	}
+
+	if title == "" {
+		title = "Task"
+	}
+
+	data := struct {
+		Title       string
+		ID          string
+		Source      string
+		Description string
+		CSRFToken   string
+		Saved       bool
+	}{title, id, source, description, auth.GetCSRFTokenFromContext(r.Context()), r.URL.Query().Get("saved") == "1"}
+
+	if err := h.renderer.Render(w, "task-detail-page.html", data); err != nil {
+		http.Error(w, "Failed to render template", http.StatusInternalServerError)
+	}
+}
+
 // HandleUpdateTask updates a task description
 func (h *Handler) HandleUpdateTask(w http.ResponseWriter, r *http.Request) {
 	if err := r.ParseForm(); err != nil {
@@ -846,7 +898,11 @@ func (h *Handler) HandleUpdateTask(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	w.WriteHeader(http.StatusOK)
+	if r.Header.Get("HX-Request") != "" {
+		w.WriteHeader(http.StatusOK)
+	} else {
+		http.Redirect(w, r, "/task?id="+id+"&source="+source+"&saved=1", http.StatusSeeOther)
+	}
 }
 
 // HandleTabTasks renders the unified Tasks tab (Todoist + Trello cards with due dates + Bugs + Google Tasks)