Reorganize repo: one folder per application under apps/.

Move docker/ and configs/ into apps/<name>/ with config/ subfolders.
Proxmox split into hosts/pve and hosts/dell-proxmox. Nginx under
infrastructure/. Update sync script, RESTORE.md, and per-app READMEs.

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

apps/homarr/docker-compose.yml

@@ -0,0 +1,17 @@
+# Homarr — startdashboard (poort 4755).
+# Configs: configs/homarr/ → /app/data/configs
+
+services:
+  homarr:
+    image: ghcr.io/ajnart/homarr:latest
+    container_name: homarr
+    restart: always
+    ports:
+      - "${HOMARR_PORT:-4755}:7575"
+    environment:
+      TZ: ${TZ:-Europe/Brussels}
+    volumes:
+      - ${HOMARR_CONFIG_DIR:-/volume1/docker/homarr}:/app/data/configs
+      - ${HOMARR_ICONS_DIR:-/volume1/docker/homarr/icons}:/app/public/icons
+      - ${HOMARR_DATA_DIR:-/volume1/docker/homarr/data}:/data
+      - /var/run/docker.sock:/var/run/docker.sock