fix(run): remove --deliberate mode per #442 kill decision

[solomonneas]

Summary

Removes the opt-in grounded-deliberation mode from brigade run per the #442 kill decision. The mode landed in #452 and was bug-fixed in #470; this deletes it in working order. Recoverable from git history.

• Drop --deliberate from brigade run and detach argv plumbing
• Delete src/brigade/deliberation.py and brigade.deliberation.v1 emission (all exports were deliberation-only; nothing moved)
• Strip aboyeur planning/synth and runs show/watch/resume surfaces
• Delete deliberation tests, including the fix(deliberation): stop passing --markdown/--limit to graph probe commands #470 probe-flag regression
• CHANGELOG Unreleased Removed entry

Historical experiment docs (docs/deliberation-experiment.md, runs/experiment/) were not on this branch and were not touched.

Closes #471. Refs #442.

Test plan

• pytest -q (full suite) via brigade work verify run
• Run-related modules suite (cli, detach, runs, resume, aboyeur, transport)
• ruff check / ruff format --check on touched files
• mypy
• CI green on this PR

[coderabbitai]

Important

Review skipped

Auto reviews are limited based on label configuration.

🏷️ Required labels (at least one) (1)

• coderabbit-review

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository: escoffier-labs/coderabbit/.coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: 91f283f6-ad21-4773-bde7-8d0a3e152f7c

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch issue/471-remove-deliberate

---

_{Comment @coderabbitai help to get the list of available commands.}