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/proxmox/hosts/pve/storage.cfg

@@ -0,0 +1,15 @@
+dir: local
+	path /var/lib/vz
+	content vztmpl,iso,backup
+
+lvmthin: local-lvm
+	thinpool data
+	vgname pve
+	content rootdir,images
+
+lvm: Storage
+	vgname Storage
+	content rootdir,images
+	nodes pve
+	shared 0
+