chore: introduce development integration workflow

[Eoic]

Summary

Enable normal CI and release-configuration checks for development integration pushes and PRs. Document feature PRs targeting development, version bumps during release preparation, and merge-commit promotion from development to master. The signed release workflow and version/build-number strategy are unchanged.

Testing

Actionlint for all client workflows, 12 fast release/signing checks, and git diff --check passed. Flutter application code is unchanged; no Flutter suite was rerun.

UI evidence

Not applicable.

Compatibility and migration

Development was created from the current master and is now the default branch. Existing versions, signing settings, deployment endpoints, and release history are unchanged.

Notes

Merge this PR into development. The pending mobile auth/Goals fixes remain separate. Release promotions must use Create a merge commit; bring master back into development afterwards.

Checklist

• The branch, commits, and pull request title follow the repository conventions.
• The change is complete and limited to the agreed scope.
• Relevant existing release checks pass; branch filters require no new application tests.
• Workflow validation and whitespace checks pass.
• Documentation, UI evidence, and migration notes are included where relevant.
• No credentials, personal data, copyrighted fixtures, or unrelated generated files are included.
• The branch is up to date with its target branch.

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-06T11:30:46.506288Z	a3d336a	PR opened

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