* remove apps/core and apps/fern
* fix precommit
* add submodule updates in workflows
* submodule
* remove core tests
* update core revision
* Add submodules: true to all GitHub workflows
- Ensure all workflows can access git submodules
- Add submodules support to deployment, test, and CI workflows
- Fix YAML syntax issues in workflow files
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
* remove core-lint
* upgrade core with latest main of oss
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Co-authored-by: Claude <noreply@anthropic.com>
