feat(sv): Storage · capacity card — ZFS pools, dropped pools, per-CT disk

Read-only Proxmox storage health (same PROXMOX_RO_TOKEN as the cluster card):
ZFS pool health+usage, dropped zfspool storages (the donatello/leonardo SATA
signal), and per-LXC rootfs fill, with a HEALTHY/WATCH/ATTENTION roll-up.
Closes the monitoring gap from the 2026-06-09 audit (C1 + H2 were invisible).
Pure normalizeStorage() unit-tested (4 tests).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

CHANGELOG.md

@@ -3,6 +3,10 @@
 All notable changes to Void 2.0 are documented here.
 Format: [Keep a Changelog](https://keepachangelog.com).
 
+## 2.4.0 — Storage · capacity card (Sacred Valley)
+- **New "Storage · capacity" card** (`public/views/cards/storage.js`, `/api/storage`, `lib/proxmox/storage.js`) — read-only Proxmox health via the same `PROXMOX_RO_TOKEN` as the cluster card. Shows: **ZFS pools** (health + usage meter), **dropped pools** (a configured zfspool storage that's no longer `available` — the donatello/leonardo SATA-bus signal, rendered red), and **per-container disk fill** (top LXC by rootfs %), with a HEALTHY/WATCH/ATTENTION roll-up badge. Thresholds: 80% warn, 90% crit; a non-ONLINE or dropped pool is always crit.
+- Closes the monitoring gap from the 2026-06-09 audit (the Void couldn't previously see C1 = pools offline or H2 = a container at 95%). Pure `normalizeStorage()` is unit-tested.
+
 ## 2.3.0 — MagicMirror² as a Void app
 - **New "MagicMirror" Apps view** (`#/mirror`, `public/views/mirror.js`) — embeds the smart-mirror dashboard (CT 111) via the shared `embedView` factory, like Timelapse / AI Usage.
 - **Exposure:** MagicMirror (LAN-only `192.168.1.224:8080`) is now published at **mirror.hynesy.com** through Traefik + the `*.hynesy.com` tunnel, private behind **CF Access** (Farm policy / Google IdP). A Traefik `mirror-frame` middleware replaces MM's `X-Frame-Options: SAMEORIGIN` with a CSP `frame-ancestors` allowing the Void origins so the iframe renders.