add express example, framework selector and use existing package.json (just update it)

create-app.ts

index.ts

templates/index.ts

templates/simple/express/README-template.md

templates/simple/express/eslintrc.json

templates/simple/express/index.ts

templates/simple/express/package.json

templates/simple/express/src/controllers/llm.controller.ts

templates/simple/express/src/routes/llm.route.ts

templates/simple/express/tsconfig.json

templates/simple/nextjs/package.json

templates/types.ts