Add start script for backend server initialization and update .gitignore

.gitignore

@@ -10,6 +10,7 @@
 .env.*
 !.env.example
 .envrc
+.sh
 
 # ===== Python =====
 # Byte-compiled / optimized / DLL files

start.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+
+# Exit immediately if a command fails
+set -e
+
+# Activate virtual environment
+source .venv/bin/activate
+
+# Start the backend
+python -m uvicorn server:app --reload --port 8000