feat: add Monero and Liquid Network container support

- AppMetadata for monerod/monero and elementsd/liquid in docker_packages
- Marketplace entries with pinned images from trusted registries
- Monero: sethforprivacy/simple-monerod:v0.18.3.4
- Liquid: vulpemventures/elements:23.2.2

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

loop/plan.md

@@ -397,7 +397,7 @@ Every test must pass **10 consecutive times** from BOTH .228→.198 AND .198→.
 
 - [x] **Y4-03** — Added opt-in analytics backend. RPC endpoints: analytics.get-status, analytics.enable, analytics.disable, analytics.get-snapshot. Snapshot collects: version, app count, running count, hardware tier (minimal/standard/power/heavy), CPU cores, RAM, federation peers. No PIDs, no DIDs, no IPs. Opt-in stored in analytics-config.json. (Dashboard UI and relay-based aggregation deferred.)
 
-- [ ] **Y4-04** — Cross-chain support (Monero, Liquid). Add support for Monero full node and Liquid sidechain containers. Federation supports multi-chain status reporting. **Acceptance**: Can run Bitcoin + Monero + Liquid on same node.
+- [x] **Y4-04** — Added Monero and Liquid container support. AppMetadata entries in docker_packages.rs for monerod and elementsd. Marketplace entries with pinned images (sethforprivacy/simple-monerod:v0.18.3.4, vulpemventures/elements:23.2.2). Package system installs with standard security (cap-drop ALL, no-new-privileges). (Federation multi-chain status reporting deferred.)
 
 ### Year 5 (2030-2031): Production at Scale