[wangtsiao]

Summary

• Remove the optional tmux-live CI job that calls real DeepSeek and OpenAI providers.
• Remove its exclusively used tmux-secrets detection job and live-provider environment configuration.
• Keep all 12 other CI job definitions unchanged, including the credential-free TUI tmux smoke job, mock-provider completed-turn test, and reusable T1/T2/T3 harness.

This follows the request to remove the optional credential-dependent test after #255 merged. Scope: one workflow file, 95 lines deleted; no product code or generic test scripts changed.

Validation

Final head: 301e969cdeb49bb295389cc2e182b60906fd7cbd, including main fdd5236b291093b45013d03742c23125d63e26f3 after #256 integrated #254.

• python -m unittest discover -s scripts -p test_ci_scope.py -v: 9 passed on the final tree.
• YAML parse and structural comparison against latest main: exactly tmux-live and tmux-secrets removed; all retained jobs and triggers unchanged; every dependency resolves; no live-job configuration references remain.
• git diff --check: passed.
• GitHub CI run 42169355334: 17/17 jobs passed.
• Runtime bundles run 42169355232: 6/6 platform jobs passed.
• All 23 executed checks passed on the final head. No jobs were skipped in these two runs.