Initial voice-assistant-stack: open-webui + spotify-voice-assistant submodules, asr/tts sidecars

- open-webui: submodule, LAN OIDC/Authentik-fronted, GPU-passthrough ollama,
  ollama-auth proxy, asr/tts wired via docker-compose.audio.yaml
- spotify-voice-assistant: submodule, Home Assistant custom integration
- tts-server / asr-server: plain directories, built as sidecars by
  open-webui/docker-stack.sh (no separate git history)

assistant-stack.code-workspace

@@ -0,0 +1,20 @@
+{
+	"folders": [
+		{
+			"path": "open-webui"
+		},
+		{
+			"path": ".venv"
+		},
+		{
+			"path": "tts-server"
+		},
+		{
+			"path": "asr-server"
+		},
+		{
+			"path": "spotify-voice-assistant"
+		}
+	],
+	"settings": {}
+}