feat(demo): add Homepage dashboard configuration files

- services.yaml: all 13 user-facing services organized by category
  with Pi-hole and Grafana widgets for live stats
- widgets.yaml: greeting, datetime, search, and Pi-hole glances widget
- bookmarks.yaml: developer resource links (GitHub, Stack Overflow,
  Docker Hub, Grafana Docs, InfluxDB Docs)
- settings.yaml: layout configuration (row style, column counts),
  Docker provider via socket proxy, and branding

Previously only docker.yaml existed, resulting in a bare-bones
dashboard with no widgets, bookmarks, or layout.

💘 Generated with Crush

Assisted-by: GLM-5.1 via Crush <crush@charm.land>

demo/config/homepage/services.yaml

@@ -0,0 +1,77 @@
+---
+# Homepage Services Configuration
+# Services are auto-discovered via Docker labels, but this provides
+# the manual layout and widget configuration.
+
+- Infrastructure:
+    - Pi-hole:
+        href: http://localhost:4006/admin
+        description: DNS management with ad blocking
+        icon: pihole.png
+        widget:
+          type: pihole
+          url: http://localhost:4006
+          password: demo_password
+
+    - Dockhand:
+        href: http://localhost:4007
+        description: Modern Docker management UI
+        icon: dockhand.png
+
+- Monitoring:
+    - InfluxDB:
+        href: http://localhost:4008
+        description: Time series database for metrics
+        icon: influxdb.png
+
+    - Grafana:
+        href: http://localhost:4009
+        description: Analytics and visualization platform
+        icon: grafana.png
+        widget:
+          type: grafana
+          url: http://localhost:4009
+          username: admin
+          password: demo_password
+
+- Documentation:
+    - Draw.io:
+        href: http://localhost:4010
+        description: Web-based diagramming application
+        icon: drawio.png
+
+    - Kroki:
+        href: http://localhost:4011
+        description: Diagrams as a service
+        icon: kroki.png
+
+- Developer Tools:
+    - Atomic Tracker:
+        href: http://localhost:4012
+        description: Habit tracking and personal dashboard
+        icon: atomic-tracker.png
+
+    - ArchiveBox:
+        href: http://localhost:4013
+        description: Web archiving solution
+        icon: archivebox.png
+
+    - Tube Archivist:
+        href: http://localhost:4014
+        description: YouTube video archiving
+        icon: tube-archivist.png
+
+    - Wakapi:
+        href: http://localhost:4015
+        description: Open-source WakaTime alternative
+        icon: wakapi.png
+
+    - MailHog:
+        href: http://localhost:4017
+        description: Web and API based SMTP testing
+        icon: mailhog.png
+
+    - Atuin:
+        href: http://localhost:4018
+        description: Magical shell history synchronization
+        icon: atuin.png