[JCLEM-39] Ignore generated app config in cookbook templates (#119)

## Description

#### Attribution
- Custom agent: [Clem
3000](https://app.dev.notion.com/agent/3e2b35e6e67f8010b001009293c9d64c?wfv=chat)
- Custom agent created by: Jonathan Clem (jclem@makenotion.com)
- Custom agent requested by: Jonathan Clem (jclem@makenotion.com)
- Notion thread: [View
thread](https://app.dev.notion.com/chat?t=3eab35e6e67f80ee9da700a9242ca12d)

Ignore local `app.json` and `workers.json` in both Apps templates so
generated config stays out of new App commits.

## How was this change tested?

- [ ] Automated test (unit, integration, etc.)
- [x] Manual test: `git check-ignore -v --no-index` matched all four
template paths; `git diff --check` passed.

## Is this feature gated? (Optional)

- [ ] Yes
- [x] No

Author: jclem

apps/templates/apps-default/.gitignore

@@ -1,4 +1,6 @@
 .notion/
+app.json
+workers.json
 dist/
 node_modules/
 package-lock.json

apps/templates/perfect-meetings/.gitignore

@@ -1,4 +1,6 @@
 .notion/
+app.json
+workers.json
 dist/
 node_modules/
 package-lock.json