Add start/stop/restart scripts and USER_GUIDE documentation

stop.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+# Stop script for AI Job Application server
+
+APP_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PID_FILE="$APP_DIR/.app.pid"
+
+if [ -f "$PID_FILE" ]; then
+    PID=$(cat "$PID_FILE")
+    if kill -0 "$PID" 2>/dev/null; then
+        echo "Stopping AI Job Application server (PID: $PID)..."
+        kill "$PID" 2>/dev/null
+        
+        # Give it a moment to shutdown gracefully
+        for i in {1..5}; do
+            if ! kill -0 "$PID" 2>/dev/null; then
+                break
+            fi
+            sleep 1
+        done
+
+        # Force kill if still running
+        if kill -0 "$PID" 2>/dev/null; then
+            echo "Force stopping PID $PID..."
+            kill -9 "$PID" 2>/dev/null
+        fi
+
+        rm -f "$PID_FILE"
+        echo "✓ Server stopped successfully."
+    else
+        echo "Server is not running (stale PID file found and removed)."
+        rm -f "$PID_FILE"
+    fi
+else
+    # Check for any rogue tsx server.ts process
+    PIDS=$(pgrep -f "tsx server.ts" || pgrep -f "dist/server.cjs")
+    if [ -n "$PIDS" ]; then
+        echo "Stopping running server process(es): $PIDS"
+        kill $PIDS 2>/dev/null
+        echo "✓ Server stopped."
+    else
+        echo "AI Job Application server is not running."
+    fi
+fi