feat: add FastAPI app with WebSocket streaming and escalation loop

tests/test_main.py

@@ -0,0 +1,32 @@
+from fastapi.testclient import TestClient
+
+from server.main import create_app
+
+
+class TestRESTEndpoints:
+    def test_status_endpoint(self):
+        """GET /status returns intensity and pool info."""
+        test_app = create_app(skip_models=True)
+        with TestClient(test_app) as client:
+            resp = client.get("/status")
+            assert resp.status_code == 200
+            data = resp.json()
+            assert "intensity" in data
+            assert "connected_clients" in data
+            assert "image_pool_size" in data
+
+    def test_reset_endpoint(self):
+        """POST /reset restarts escalation."""
+        test_app = create_app(skip_models=True)
+        with TestClient(test_app) as client:
+            resp = client.post("/reset")
+            assert resp.status_code == 200
+            assert resp.json()["status"] == "ok"
+
+    def test_index_serves_html(self):
+        """GET / serves the frontend HTML (or fallback)."""
+        test_app = create_app(skip_models=True)
+        with TestClient(test_app) as client:
+            resp = client.get("/")
+            assert resp.status_code == 200
+            assert "text/html" in resp.headers["content-type"]