Add global web nav with project groups and tree sidebar.

Restructure the UI into top-level tabs and a scrollable project tree, and persist optional project groups so demos and settings can organize many projects.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/server/seed.go

@@ -3,6 +3,7 @@ package server
 import (
 	"fmt"
 	"os"
+	"strings"
 	"time"
 
 	"task/internal/sqlite"
@@ -78,13 +79,26 @@ func (s *Server) SeedDemo() error {
 			},
 		},
 	}
+	for i := len(demos) + 1; i <= 50; i++ {
+		demos = append(demos, struct {
+			Name    string
+			Tickets []seedTicket
+		}{
+			Name: fmt.Sprintf("Sample %02d", i),
+			Tickets: []seedTicket{
+				{Title: "Starter ticket", Desc: "Seed-Platzhalter.", Status: ticket.StatusTodo},
+			},
+		})
+	}
 
 	now := time.Now().UTC()
+	created := make([]struct{ ID, Name string }, 0, len(demos))
 	for _, d := range demos {
 		p, err := s.Projects.Create("", d.Name)
 		if err != nil {
 			return err
 		}
+		created = append(created, struct{ ID, Name string }{p.ID, p.Name})
 		_ = s.DB.SetMember(p.ID, admin.ID, sqlite.RoleOwner)
 		_ = s.DB.SetMember(p.ID, member.ID, sqlite.RoleMember)
 		// Explicit local-only sync (no remote backend in the test environment).
@@ -125,6 +139,23 @@ func (s *Server) SeedDemo() error {
 		}
 	}
 
-	fmt.Fprintf(os.Stderr, "seeded demo: Test + sample projects (users %s + alice/alice), sync=none\n", admin.Username)
+	kunden, err := s.DB.CreateProjectGroup("Kunden")
+	if err != nil {
+		return fmt.Errorf("seed group Kunden: %w", err)
+	}
+	intern, err := s.DB.CreateProjectGroup("Intern")
+	if err != nil {
+		return fmt.Errorf("seed group Intern: %w", err)
+	}
+	for _, c := range created {
+		switch {
+		case c.Name == "Website Relaunch" || c.Name == "API Platform" || strings.HasPrefix(c.Name, "Sample 0"):
+			_ = s.Projects.SetGroup(c.ID, kunden.ID)
+		case c.Name == "Test" || strings.HasPrefix(c.Name, "Sample 1") || strings.HasPrefix(c.Name, "Sample 2"):
+			_ = s.Projects.SetGroup(c.ID, intern.ID)
+		}
+	}
+
+	fmt.Fprintf(os.Stderr, "seeded demo: %d projects, 2 groups (users %s + alice/alice), sync=none\n", len(demos), admin.Username)
 	return nil
 }