chore(example): add @auth/express example app (#9570)
* feat: add @auth/express dev app
* test: add signin e2e spec
* chore: update pnpm-lock
* refactor: move express app to examples
* chore: rename files plus load env before import app
* chore: update signed in layout banner
* chore: update pnpm-lock
* chore: add comment for credentials validator
* fix: missing pug view engine
* chore: cleanup server callbacks
* chore: update dev concurrently tags
* docs: standardize express auth example readme
* chore: update error handler errors
* test: no e2e in example
* chore: cleanup scripts
* docs: add section on node.js compatibility to express example
* chore: remove credentials provider
* docs: add comment on rate-limiting for authentication routes
* chore: use AuthConfig type
* chore: add node engine plus remove experimental flags
* refactor: cleanup globals
* chore: tsconfig module + moduleResolution -> nodenext to support cjs require
* docs: remove experimental fetch discussion and include crypto polyfill
* chore: temp include @auth/core dep
* chore: remove name and version
* chore: update gitignore
* docs: update express img link
* chore: add node types
* feat: vercel ready express example
* chore: cleanup
* docs: update host copy
* chore: remove @auth/core dependency
* chore: add viewport meta
* feat: sync example app
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Co-authored-by: Nico Domino <yo@ndo.dev>
