## Description
This PR ensures that the default prettier config is used for examples
and templates.
This config is compatible with `prettier@3` as well (upgrading prettier
is bigger change that can be a future PR).
## Changes
- Updated `.prettierrc.json` in root with `"trailingComma": "es5"` (will
be needed upgrading to prettier@3)
- Added `examples/.prettierrc.json` with default config (this will
change every example)
- Added `packages/create-next-app/templates/.prettierrc.json` with
default config (this will change every template)
## Related
- Fixes#54402
- Closes#54409
Strategized with @balazsorban44 to open one larger PR, with changes to individual examples as separate commits.
For each example, I researched how multiple realworld codebases use the featured technology with TypeScript, to thoughtfully convert them by hand - nothing automated whatsoever.
## Documentation / Examples
- [X] Make sure the linting passes by running `pnpm lint`
- [X] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)
