refactor: finish the AgentHub rename and drop the MCP server

Two leftovers from the rebrand, done together because they touch the same
docs and manifests.

**Data directory.** `agent-dashboard` could not simply be renamed in the
source: it names a real directory holding the live SQLite database. Startup
now moves it once, via `migrateLegacyDataDir()` in `server/lib/claude-home.js`
— a same-filesystem rename, so it is instant even at multiple gigabytes and
cannot leave two divergent copies. `getDataDir()` stays PURE and resolves to
the legacy path until the move happens; the first version of this put the
rename inside the getter, which meant `npm run test:server` relocated the
developer's real database as a side effect. The call sits behind
`require.main === module` and ahead of the router requires, because those pull
in db.js, which opens SQLite at module load. A failed rename is silent and the
old directory keeps being used: an unfashionable directory name beats a blank
database beside an unreachable one. Same treatment for the port-discovery file
(`.agent-dashboard.json` → `.agenthub.json`, old one dropped on write).

Not renamed on purpose: the Sagi localStorage keys (renaming silently resets
everyone's prefs) and the PWA manifest `id` (changing it orphans an installed
app).

**MCP server.** 4 tool calls in 46 days across 577,132 events, against 4,556
lines of TypeScript, a 2 MB committed build artifact, and a pre-commit guard
that had already blocked commits twice. Deleted: `mcp/`, the maintainer skills
and `mcp-reviewer` agent, the build check, `plugins/agenthub/.mcp.json`,
`docs/MCP.md`, 12 npm scripts, 5 Makefile targets, and every doc section
describing it.

Kept, because they are unrelated things sharing the name: the Config
Explorer's MCP tab and its API, per-lane Playwright MCP, the agenthub-config
plugin's MCP audit, and the historical `mcp__plugin_agenthub_*` events that
analytics must keep attributing.

Verified: server 1432/1432, client 459/459, tsc clean, prettier clean. Both
directions of the migration proven — a sandbox-HOME test run leaves the legacy
directory untouched, and a real boot moves it with its contents intact.

docs/DEPLOYMENT.md

@@ -149,8 +149,8 @@ graph TB
 
 ```bash
 # Clone repository
-git clone https://github.com/your-org/agent-dashboard.git
-cd agent-dashboard
+git clone https://github.com/your-org/agenthub.git
+cd agenthub
 
 # Install dependencies
 npm run setup
@@ -190,7 +190,6 @@ npm run dev:server
 npm run dev:client
 
 # Terminal 3: MCP server (optional)
-npm run mcp:dev
 ```
 
 ---
@@ -225,10 +224,10 @@ npm run build
 # 3. Set environment variables
 export NODE_ENV=production
 export PORT=4820
-export DASHBOARD_DB_PATH=/var/lib/agent-dashboard/dashboard.db
+export DASHBOARD_DB_PATH=/var/lib/agenthub/dashboard.db
 
 # 4. Create data directory
-mkdir -p /var/lib/agent-dashboard
+mkdir -p /var/lib/agenthub
 
 # 5. Start server
 node server/index.js
@@ -250,7 +249,7 @@ DASHBOARD_TOKEN=                        # required on /api/* + WS when set; use
 DASHBOARD_ALLOWED_HOSTS=                # extra Host names (comma-sep) for a LAN bind
 
 # Database
-DASHBOARD_DB_PATH=/var/lib/agent-dashboard/dashboard.db
+DASHBOARD_DB_PATH=/var/lib/agenthub/dashboard.db
 
 # Ingestion polls (0 disables either one)
 DASHBOARD_WORKFLOW_POLL_MS=12000        # Workflow-tool run journals
@@ -278,7 +277,7 @@ LOG_LEVEL=info                         # debug | info | warn | error
 version: '3.8'
 
 services:
-  agent-dashboard:
+  agenthub:
     build: .
     ports:
       - "4820:4820"
@@ -382,7 +381,7 @@ graph TB
 pip install awsebcli
 
 # Initialize
-eb init -p node.js agent-dashboard
+eb init -p node.js agenthub
 
 # Create environment
 eb create production
@@ -401,20 +400,20 @@ eb open
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: agent-dashboard
+  name: agenthub
 spec:
   replicas: 3
   selector:
     matchLabels:
-      app: agent-dashboard
+      app: agenthub
   template:
     metadata:
       labels:
-        app: agent-dashboard
+        app: agenthub
     spec:
       containers:
-      - name: agent-dashboard
-        image: agent-dashboard:latest
+      - name: agenthub
+        image: agenthub:latest
         ports:
         - containerPort: 4820
         env:
@@ -426,16 +425,16 @@ spec:
       volumes:
       - name: data
         persistentVolumeClaim:
-          claimName: agent-dashboard-pvc
+          claimName: agenthub-pvc
 
 ---
 apiVersion: v1
 kind: Service
 metadata:
-  name: agent-dashboard
+  name: agenthub
 spec:
   selector:
-    app: agent-dashboard
+    app: agenthub
   ports:
   - protocol: TCP
     port: 80
@@ -453,9 +452,9 @@ graph TB
         end
         
         subgraph "Pods"
-            Pod1[agent-dashboard-1<br/>:4820]
-            Pod2[agent-dashboard-2<br/>:4820]
-            Pod3[agent-dashboard-3<br/>:4820]
+            Pod1[agenthub-1<br/>:4820]
+            Pod2[agenthub-2<br/>:4820]
+            Pod3[agenthub-3<br/>:4820]
         end
         
         subgraph "Storage"
@@ -488,22 +487,22 @@ graph TB
 npm install -g pm2
 
 # Start application
-pm2 start server/index.js --name agent-dashboard
+pm2 start server/index.js --name agenthub
 
 # Start with environment
-pm2 start server/index.js --name agent-dashboard --env production
+pm2 start server/index.js --name agenthub --env production
 
 # View logs
-pm2 logs agent-dashboard
+pm2 logs agenthub
 
 # Monitor
 pm2 monit
 
 # Restart
-pm2 restart agent-dashboard
+pm2 restart agenthub
 
 # Stop
-pm2 stop agent-dashboard
+pm2 stop agenthub
 
 # Auto-start on system boot
 pm2 startup
@@ -516,7 +515,7 @@ pm2 save
 // ecosystem.config.js
 module.exports = {
   apps: [{
-    name: 'agent-dashboard',
+    name: 'agenthub',
     script: './server/index.js',
     instances: 2,
     exec_mode: 'cluster',
@@ -527,11 +526,11 @@ module.exports = {
     env_production: {
       NODE_ENV: 'production',
       PORT: 4820,
-      DASHBOARD_DB_PATH: '/var/lib/agent-dashboard/dashboard.db'
+      DASHBOARD_DB_PATH: '/var/lib/agenthub/dashboard.db'
     },
     max_memory_restart: '500M',
-    error_file: '/var/log/agent-dashboard/error.log',
-    out_file: '/var/log/agent-dashboard/out.log',
+    error_file: '/var/log/agenthub/error.log',
+    out_file: '/var/log/agenthub/out.log',
     time: true
   }]
 };
@@ -545,18 +544,18 @@ pm2 start ecosystem.config.js --env production
 ### Systemd Service (Linux)
 
 ```ini
-# /etc/systemd/system/agent-dashboard.service
+# /etc/systemd/system/agenthub.service
 [Unit]
 Description=Agent Dashboard
 After=network.target
 
 [Service]
 Type=simple
-User=agent-dashboard
-WorkingDirectory=/opt/agent-dashboard
+User=agenthub
+WorkingDirectory=/opt/agenthub
 Environment=NODE_ENV=production
 Environment=PORT=4820
-Environment=DASHBOARD_DB_PATH=/var/lib/agent-dashboard/dashboard.db
+Environment=DASHBOARD_DB_PATH=/var/lib/agenthub/dashboard.db
 ExecStart=/usr/bin/node server/index.js
 Restart=on-failure
 RestartSec=10
@@ -569,14 +568,14 @@ WantedBy=multi-user.target
 
 ```bash
 # Enable and start service
-sudo systemctl enable agent-dashboard
-sudo systemctl start agent-dashboard
+sudo systemctl enable agenthub
+sudo systemctl start agenthub
 
 # Check status
-sudo systemctl status agent-dashboard
+sudo systemctl status agenthub
 
 # View logs
-sudo journalctl -u agent-dashboard -f
+sudo journalctl -u agenthub -f
 ```
 
 ---
@@ -680,8 +679,8 @@ graph TB
 #!/bin/bash
 # scripts/backup.sh
 
-BACKUP_DIR="/var/backups/agent-dashboard"
-DB_PATH="/var/lib/agent-dashboard/dashboard.db"
+BACKUP_DIR="/var/backups/agenthub"
+DB_PATH="/var/lib/agenthub/dashboard.db"
 TIMESTAMP=$(date +%Y%m%d_%H%M%S)
 BACKUP_FILE="$BACKUP_DIR/dashboard_$TIMESTAMP.db"
 
@@ -695,7 +694,7 @@ sqlite3 "$DB_PATH" "VACUUM INTO '$BACKUP_FILE'"
 gzip "$BACKUP_FILE"
 
 # Upload to S3 (optional)
-aws s3 cp "$BACKUP_FILE.gz" s3://my-backups/agent-dashboard/
+aws s3 cp "$BACKUP_FILE.gz" s3://my-backups/agenthub/
 
 # Delete old backups (keep last 7 days)
 find "$BACKUP_DIR" -name "dashboard_*.db.gz" -mtime +7 -delete
@@ -710,7 +709,7 @@ echo "Backup completed: $BACKUP_FILE.gz"
 # scripts/restore.sh
 
 BACKUP_FILE=$1
-DB_PATH="/var/lib/agent-dashboard/dashboard.db"
+DB_PATH="/var/lib/agenthub/dashboard.db"
 
 if [ -z "$BACKUP_FILE" ]; then
   echo "Usage: ./restore.sh <backup_file.db.gz>"
@@ -718,17 +717,17 @@ if [ -z "$BACKUP_FILE" ]; then
 fi
 
 # Stop application
-systemctl stop agent-dashboard
+systemctl stop agenthub
 
 # Decompress backup
 gunzip -c "$BACKUP_FILE" > /tmp/restore.db
 
 # Restore database
 cp /tmp/restore.db "$DB_PATH"
-chown agent-dashboard:agent-dashboard "$DB_PATH"
+chown agenthub:agenthub "$DB_PATH"
 
 # Start application
-systemctl start agent-dashboard
+systemctl start agenthub
 
 echo "Restore completed from $BACKUP_FILE"
 ```
@@ -767,7 +766,7 @@ graph TB
 ### TLS Configuration (Nginx Reverse Proxy)
 
 ```nginx
-# /etc/nginx/sites-available/agent-dashboard
+# /etc/nginx/sites-available/agenthub
 server {
     listen 443 ssl http2;
     server_name dashboard.example.com;