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/qemu-server/111.conf

@@ -0,0 +1,17 @@
+agent: 1
+boot: order=sata0
+cores: 1
+cpu: x86-64-v2-AES
+ide2: none,media=cdrom
+memory: 4098
+meta: creation-qemu=10.0.2,ctime=1763556365
+name: Syno-latest
+net0: virtio=BC:24:11:E4:40:80,bridge=vmbr0,firewall=1
+numa: 0
+ostype: l26
+sata0: local-lvm:vm-111-disk-0,size=1852M
+sata1: Storage:vm-111-disk-0,size=32G
+scsihw: virtio-scsi-single
+smbios1: uuid=507c91d7-8db0-414e-bc1d-448477494e19
+sockets: 1
+vmgenid: da2426b2-fe55-4809-9280-57c9503b3baa