Initial commit: LlamaLink Go rewrite

Complete rewrite from Python/FastAPI to Go/Gin:
- Go backend: auth (API keys + bcrypt), llama.cpp subprocess manager,
  hot-swap multi-model, rate limiting, quota system, webhooks
- Vue 3 SPA admin panel (src/) with Tailwind CSS
- Deployment: Docker multi-stage, docker-compose, nginx, systemd
- GORM/SQLite models: ApiKey, Model, UsageLog, Quota, Webhook
- REST API: /api/v1/admin/* (keys, models, chat, usage, health)
- Embedded frontend via go:embed (build output at web/dist/)

Removed legacy Python artifacts (app/, tests/, pyproject.toml, etc.)

deploy/llamalink.service

@@ -0,0 +1,28 @@
+[Unit]
+Description=LlamaLink API Gateway
+After=network.target
+
+[Service]
+Type=simple
+User=llamalink
+WorkingDirectory=/opt/llamalink
+ExecStart=/usr/local/bin/llamalink \
+    --host 0.0.0.0 \
+    --port 8000
+Restart=on-failure
+RestartSec=5
+StandardOutput=journal
+StandardError=journal
+SyslogIdentifier=llamalink
+
+# Security
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+ReadWritePaths=/opt/llamalink/data
+ReadOnlyPaths=/opt/llamalink/models
+Environment=LLAMALINK_ENV=production
+
+[Install]
+WantedBy=multi-user.target