fix: gitignore + testing map structure

ref: N25B-205

src/control_backend/api/v1/endpoints/sse_ping.py

@@ -0,0 +1,26 @@
+from fastapi import APIRouter, Request
+from fastapi.responses import StreamingResponse
+import datetime
+import asyncio
+
+router = APIRouter()
+
+@router.get("/sse_ping")
+async def sse_ping(request: Request):
+    """
+    Endpoint for Server-Sent Events.
+    """
+    async def event_generator():
+        while True:
+            # If connection to client closes, stop sending events
+            if await request.is_disconnected():
+                break
+            
+            # Send message containing current time every second
+            current_time = datetime.datetime.now().strftime("%H:%M:%S")
+            yield f"data: Server time: {current_time}\n\n" # \n\n is needed to separate events (SSE is text-based)
+            await asyncio.sleep(1)
+
+    return StreamingResponse(event_generator(), media_type="text/event-stream") # media_type specifies that this connection is for event streams
+
+