refactor: flatten monorepo structure to backend/ frontend/ devops/

Rename subdirectories for a cleaner single-repo layout:
- website-monitoring-backend/  → backend/
- website-monitoring-frontend/ → frontend/
- website-monitoring-devops/   → devops/

Update all references in package.json scripts, CI workflows,
docker-compose, pre-commit hooks, and documentation.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

devops/.devcontainer/setup-repos.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+
+# Working directory setup
+cd /workspaces
+
+# Clone repositories if they don't exist
+if [ ! -d "/workspaces/frontend" ]; then
+  echo "Cloning Frontend repository..."
+  git clone https://github.com/DEINUSERNAME/website-monitoring-frontend /workspaces/frontend
+fi
+
+if [ ! -d "/workspaces/backend" ]; then
+  echo "Cloning Backend repository..."
+  git clone https://github.com/DEINUSERNAME/website-monitoring-backend /workspaces/backend
+fi
+
+# Install dependencies
+echo "Installing frontend dependencies..."
+cd /workspaces/frontend
+npm install
+
+echo "Installing backend dependencies..."
+cd /workspaces/backend
+npm install
+
+echo "Workspace setup complete!"