Fix dashboard black screen, add login gate, and expand README.

Pin React Three Fiber to React 18, remove PWA caching, add SessionGate and error boundaries, and document movie fusion, auth, outputs, and troubleshooting.

server/web/src/components/Visual/3D/FleetTopologyMap.tsx

@@ -1,5 +1,5 @@
 import { Canvas, useFrame } from '@react-three/fiber';
-import { OrbitControls, Stars, Line, Sphere, Text } from '@react-three/drei';
+import { OrbitControls, Stars, Line, Sphere } from '@react-three/drei';
 import { useMemo, useRef } from 'react';
 import * as THREE from 'three';
 import { Agent } from '../../../types';
@@ -48,12 +48,6 @@ function AgentNode({ agent, position, serverPos }: { agent: Agent, position: [nu
       <Sphere ref={pulseRef} args={[0.3, 16, 16]}>
         <meshStandardMaterial color={color} emissive={color} emissiveIntensity={isOnline ? (isHashing ? 2 : 1) : 0.2} wireframe />
       </Sphere>
-      <Text position={[0, -0.6, 0]} fontSize={0.2} color="white" anchorX="center" anchorY="middle">
-        {agent.name}
-      </Text>
-      <Text position={[0, -0.85, 0]} fontSize={0.15} color={color} anchorX="center" anchorY="middle">
-        {isOnline ? `${(agent.hashrate_15m).toFixed(0)} H/s` : 'OFFLINE'}
-      </Text>
       {/* Connection Line */}
       <Line points={[[0,0,0], [serverPos[0] - position[0], serverPos[1] - position[1], serverPos[2] - position[2]]]} color={isOnline ? '#004455' : '#330000'} lineWidth={1} transparent opacity={0.4} />
       
@@ -101,9 +95,6 @@ export default function FleetTopologyMap({ agents }: { agents: Agent[] }) {
           <Sphere args={[0.3, 16, 16]}>
             <meshStandardMaterial color="#ffffff" emissive="#ffffff" emissiveIntensity={2} />
           </Sphere>
-          <Text position={[0, -1.2, 0]} fontSize={0.35} color="#ffb020" anchorX="center" anchorY="middle">
-            MOTHERSHIP
-          </Text>
         </group>
 
         {/* Agent Nodes */}