feat: rework to use next and host from single dockerfile

main.py

@@ -1,9 +1,14 @@
 import logging
-import uvicorn
+import os
+from pathlib import Path
 
+import uvicorn
 from dotenv import load_dotenv
 from fastapi import FastAPI
+from fastapi.staticfiles import StaticFiles
+from fastapi.responses import FileResponse
 from starlette.middleware.cors import CORSMiddleware
+
 from mta_sign_server.router import router as default_router
 from mta_sign_server.mta.router import router as mta_router
 from mta_sign_server.config.router import router as config_router
@@ -22,5 +27,33 @@ app.include_router(config_router)
 
 logger = logging.getLogger("main")
 
+# Serve static files from the Next.js build output
+# In production, the 'static' directory contains the built frontend
+# Set FRONTEND_ENABLE=false to disable serving static files
+frontend_enabled = os.getenv("FRONTEND_ENABLE", "true").lower() not in ("false", "0", "no")
+static_dir = Path(__file__).parent / "static"
+if frontend_enabled and static_dir.exists():
+    # Serve Next.js static assets (_next directory)
+    next_static = static_dir / "_next"
+    if next_static.exists():
+        app.mount("/_next", StaticFiles(directory=str(next_static)), name="next-static")
+
+    # Serve other static files (images, etc.)
+    app.mount("/static", StaticFiles(directory=str(static_dir)), name="static")
+
+    @app.get("/")
+    async def serve_index():
+        """Serve the main index.html for the SPA"""
+        return FileResponse(static_dir / "index.html")
+
+    @app.get("/{path:path}")
+    async def serve_spa(path: str):
+        """Serve static files or fall back to index.html for SPA routing"""
+        file_path = static_dir / path
+        if file_path.exists() and file_path.is_file():
+            return FileResponse(file_path)
+        # Fall back to index.html for client-side routing
+        return FileResponse(static_dir / "index.html")
+
 if __name__ == "__main__":
     uvicorn.run("main:app", host="0.0.0.0", port=8000, log_level="info", reload=True)