restructure: move proxmox/ into subfolder, add pihole/ section

All existing content moved from repo root into proxmox/ to make room
for other Debian machine configs. Adds pihole/ with:

- config/pihole.toml — snapshot of current Pi-hole v6 config
- config/dnsmasq.d/99-ipxe-chainload.conf — custom PXE DHCP rules
  (EFI/BIOS iPXE chainload, fixed tag-specificity bug for UEFI boot)
- pull-config.sh <source-host> <dest-dir> — pull live config to disk
- apply-config.sh <source-dir> <dest-host> — push config to a Pi-hole

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XRzqNDrbnYR22ZgZj1Bg3s

proxmox/scripts/lib/nag-patch.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+# Neutralizes the Proxmox "No valid subscription" nag (login popup and the
+# dashboard subscription indicator) by patching proxmox-widget-toolkit's
+# proxmoxlib.js. Cosmetic only - doesn't create or spoof a subscription
+# anywhere except this UI check.
+#
+# This file is not run from the repo directly - disable-subscription-nag.sh
+# installs a copy of it to /usr/local/sbin and wires it into an apt
+# Post-Invoke hook, because a proxmox-widget-toolkit package upgrade
+# overwrites proxmoxlib.js and reverts the patch. Idempotent: exits quietly
+# if already patched or if the file isn't present.
+set -euo pipefail
+
+JS_FILE="/usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js"
+[ -f "$JS_FILE" ] || exit 0
+
+PATTERN="data.status.toLowerCase() !== 'active'"
+grep -qF "$PATTERN" "$JS_FILE" || exit 0
+
+cp "$JS_FILE" "${JS_FILE}.bak.$(date +%s)"
+sed -i "s/${PATTERN}/false/g" "$JS_FILE"
+echo "Patched subscription nag in $JS_FILE"