[teamleaderleo]

Fixes a base compile red. feat-cmux-next stopped compiling the acpmux library at hub/bg_tasks.rs:160 (cannot find value result_line in this scope). Every fleet Release compile from 7da5453 onward has failed with it, including PR heads that merge the current base.

Cause: two PRs that each compiled on their own. #33779 moved the body of bg_start into a new bg_start_with_id, which has no result_line parameter. #33347 added result_line to that body. After both landed, bg_start takes result_line but never passes it on.

Fix: bg_start_with_id takes result_line and bg_start passes it through. The workflow caller (workflow_activity.rs) passes false, which is what its launch got before #33347. This is the minimal fix, so it also carries #[allow(clippy::too_many_arguments)], as other hub methods do.

cmux-ci on fleet Linux: cargo clippy -p acpmux --lib -D warnings is clean, and cargo test -p acpmux --lib -- bg_ workflow has 103 passed, 0 failed.
Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Fixes the acpmux compile red on feat-cmux-next by threading result_line through bg_start_with_id.

Two PRs that each compiled on their own broke the build after landing: one moved the body of bg_start into bg_start_with_id without a result_line parameter, and the other added result_line to that body. The fix gives bg_start_with_id a result_line parameter and has bg_start pass it through. The workflow caller in workflow_activity.rs passes false, matching its behavior before the parameter was introduced. Clippy and bg workflow tests pass locally.

^{Written for commit b0990fe. Summary will update on new commits.}

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[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review b0990fe: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr34058 -f ref=fix/acpmux-bg-result-line -f platform=macos -f backend_mode=local

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4168460606701 (2e9aa60ffa)
• cmux NEXT nightly 1.0.0-nightly.4168717571501 (4ca639b0ca)
• cmux NEXT nightly 1.0.0-nightly.4168960686802 (6076a8e983)
• cmux NEXT nightly 1.0.0-nightly.4169064870802 (3bfe74f2e0)

The feat-cmux-next push run https://github.com/manaflow-ai/cmux/actions/runs/41680509635 at 2b865bc failed: cmux-next checks (god files, concurrency, crash safety, l10n).
Those jobs last passed at e3bb5b2. This pull request is one of 1 merged since: #34058.
If the failure is in your change, fix forward on feat-cmux-next. Pull requests run only the tiers their paths reach (docs/ci/cmux-next-tiers.md); label a batch PR full-ci to run them all before merging.

[teamleaderleo]

Owned by an agent session · session

[teamleaderleo]

Review (subagent claude-sonnet-5-5): SHIP at b0990fe

Both callers of bg_start_with_id are updated. The workflow caller passes false, which matches its behaviour before #33347 (result_line only adds a lastLine summary). The diff has nothing else.
Follow-ups: none

[teamleaderleo]

Review (codex, router-review): SHIP at b0990fe

Reviewer: codex gpt-6.1-sol xhigh, fast tier.

SHIP at b0990fe
Visual verdict: unchanged by this diff

All bg_start_with_id callers now pass the new parameter, and bg_start forwards result_line correctly.

Follow-ups: none