Add update mechanism: update.sh script, project upgrade option in onboarding, update instructions in README, Bug 12

update.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+set -e
+
+FRAMEWORK_DIR="$HOME/.agent-framework"
+
+if [ ! -d "$FRAMEWORK_DIR" ]; then
+  echo "ERROR: agent-framework not installed at $FRAMEWORK_DIR"
+  echo "Run './install.sh' first."
+  exit 1
+fi
+
+echo "Updating agent-framework at $FRAMEWORK_DIR..."
+cd "$FRAMEWORK_DIR"
+
+# Check if it's a git repo
+if [ ! -d ".git" ]; then
+  echo "ERROR: $FRAMEWORK_DIR is not a git repository."
+  echo "Cannot update. Please reinstall from git."
+  exit 1
+fi
+
+# Fetch latest changes
+git fetch origin
+echo ""
+
+# Check for local changes
+if ! git diff --quiet HEAD; then
+  echo "WARNING: You have uncommitted changes in $FRAMEWORK_DIR."
+  echo "These will be lost when pulling updates."
+  read -p "Do you want to discard your local changes and update? (y/N) " -n 1 -r
+  echo
+  if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+    echo "Update cancelled."
+    exit 1
+  fi
+  git reset --hard HEAD
+fi
+
+# Pull latest changes
+git pull origin main
+echo ""
+
+echo "Update complete."
+echo "You can check for breaking changes at: https://gitea.yourdomain.com/hermes/agent-framework"