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/llama-server@.service

@@ -0,0 +1,35 @@
+[Unit]
+Description=llama-server instance %i
+After=network.target
+
+[Service]
+Type=simple
+User=llamalink
+WorkingDirectory=/opt/llamalink
+ExecStart=/usr/local/bin/llama-server \
+    --model /opt/llamalink/models/%i.gguf \
+    --alias %i \
+    --host 127.0.0.1 \
+    --port 8080 \
+    --ctx-size 8192 \
+    --n-gpu-layers auto \
+    --parallel 4 \
+    --rope-scaling linear
+Restart=on-failure
+RestartSec=5
+StandardOutput=journal
+StandardError=journal
+SyslogIdentifier=llama-server-%i
+
+Environment="CUDA_VISIBLE_DEVICES=0"
+
+# Security hardening
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=true
+ReadOnlyPaths=/opt/llamalink/models
+ReadWritePaths=/opt/llamalink/data
+
+[Install]
+WantedBy=multi-user.target