Fix Human Review Done handoff correctness

[cursor]

Summary

• Route Human Review confirmation through the orchestrator so Done hooks, merge gate fallback, wiki sweep counting, notifications, and workspace cleanup run from one path.
• Preserve Human Review workspaces during startup terminal cleanup.
• Keep retry-budget exhaustion on Blocked when a Blocked lane exists, instead of misrouting failures to Human Review.

Type

• Bug fix
• Feature
• Docs
• Tests or tooling
• Refactor

Verification

Paste the commands you ran and the result.

/tmp/symphony-validate-venv/bin/python -m pytest tests/test_orchestrator_max_retries.py tests/test_orchestrator_dispatch.py::test_confirm_done_runs_done_side_effects tests/test_orchestrator_dispatch.py::test_startup_terminal_cleanup_preserves_human_review_workspace tests/test_tui.py::test_confirm_done_hotkey_uses_orchestrator_on_human_review_card tests/test_server_routes.py::test_confirm_done_route_delegates_to_orchestrator tests/test_board_viewer.py::test_card_renderer_has_human_review_confirm_action
# 11 passed

/tmp/symphony-validate-venv/bin/python -m pytest tests/test_orchestrator_max_retries.py tests/test_orchestrator_dispatch.py tests/test_tui.py tests/test_server_routes.py tests/test_board_viewer.py
# 173 passed

/tmp/symphony-validate-venv/bin/python -m pytest
# 811 passed

For workflow/service/board changes:

symphony doctor ./WORKFLOW.md
# Not run: this checkout has no /workspace/kanban board root and may lack agent CLIs in the cloud validation environment.

Risk Notes

• Board viewer confirmation now proxies to the Symphony orchestrator endpoint so it cannot silently mark Done while the service-side Done pipeline is unavailable.
• The template checklist mentions dev, but this automation task is configured for branch cursor/critical-correctness-bugs-3dcd with base main.

Checklist

• This PR targets dev.
• I added or updated tests for behavior changes.
• I updated docs/examples for user-facing changes.
• I did not commit secrets, logs, local run state, virtualenvs, or generated artifacts.
• CI is green or I explained any expected failure above.