Builder routing: rebases go to a builder who can't push (0/5 ok), and the picker sends 23 of 23 picks to Scout (5 slots run 1 builder) #7016

Rebases now go to the builder who can push the pull's branch, and the builder picker no longer waits on a busy favourite. Tick lines read like active=1 slots=5 idle=3.

Rebases of approved, conflicted pulls (src/crew/finishing.ts)

• ownBuilder now tries, in order: the owner of the fork the branch lives in (pull.headRepoId), then the pull's author, then the agent assigned to it, then the least-busy builder.
• If that builder is busy, the rebase waits behind their current run. The round-robin lending from #6140 (lentBuilder) is deleted, since a lent builder could never push to the author's fork; that is how Torque went 0 for 5. The for field it added to the log line is gone too.
• Two failed rebases are now counted against the builder who ran them, before the pull is handed to a person.

Picking a builder for new work (src/crew/route.ts)

• The new rankedBuilder treats the decider's per-builder probabilities as a ranking. The highest-ranked builder with nothing in flight takes the issue; if every builder is busy, the favourite does.
• An issue already assigned to a builder keeps that builder.
• p now reports the decider's probability for the builder who actually took the issue.

Tick line (src/crew/autonomy.ts)

• New idle field: the builders with nothing in flight (idleBuilders), shown beside active and slots, so the limit on active is visible in the tick line.
• driveRepo still starts one issue per 60-second tick. Starting several per tick would mean rewriting the 71 tests that expect one pick per call. With the ranking fix, each tick goes to a different idle builder, so active climbs to min(slots, startable, idle builders) within a few ticks.

Tests

• test/rebase-lane.test.ts: I replaced the #6140 test "a busy builder's rebases go to idle builders". It pinned the behaviour this issue reverses, so the test was wrong for the new rule, not the code. The new tests cover the fork owner → author → assignee order and a busy author keeping the rebase.
• test/finishing-pages.test.ts: the approved conflicted pull's author, Mason, is busy while Torque is idle; the rebase is still queued for Mason. The old lending code would have given it to Torque, so this test fails without the fix.
• test/decide.test.ts: with Scout preferred but busy and Mason idle, Mason takes the issue; with both busy, Scout does.
• test/crew-ranked-pick.test.ts (new): the same case end to end through driveRepo, plus the idle count.

The type check is clean. The crew, decide, rebase-lane, finishing, tell and autonomy suites ran with 469 of 470 passing. The one failure is crew-sandbox-real.test.ts, which stops at load because this sandbox has no rg; the forge's check runs it. docs/FLOW.md now describes both rules.

To see it on the preview, watch the crew log. Rebase lines should name the pull's author as builder= and no longer carry for=. The picked lines should spread across builders as idle falls.

🤖 Generated with Claude Code

Closes #7006

Rebases now go to the builder who can push the pull's branch, and the builder picker no longer waits on a busy favourite. Tick lines read like active=1 slots=5 idle=3.

Rebases of approved, conflicted pulls (src/crew/finishing.ts)

• ownBuilder now tries, in order: the owner of the fork the branch lives in (pull.headRepoId), then the pull's author, then the agent assigned to it, then the least-busy builder.
• If that builder is busy, the rebase waits behind their current run. The round-robin lending from #6140 (lentBuilder) is deleted, since a lent builder could never push to the author's fork; that is how Torque went 0 for 5. The for field it added to the log line is gone too.
• Two failed rebases are now counted against the builder who ran them, before the pull is handed to a person.

Picking a builder for new work (src/crew/route.ts)

• The new rankedBuilder treats the decider's per-builder probabilities as a ranking. The highest-ranked builder with nothing in flight takes the issue; if every builder is busy, the favourite does.
• An issue already assigned to a builder keeps that builder.
• p now reports the decider's probability for the builder who actually took the issue.

Tick line (src/crew/autonomy.ts)

• New idle field: the builders with nothing in flight (idleBuilders), shown beside active and slots, so the limit on active is visible in the tick line.
• driveRepo still starts one issue per 60-second tick. Starting several per tick would mean rewriting the 71 tests that expect one pick per call. With the ranking fix, each tick goes to a different idle builder, so active climbs to min(slots, startable, idle builders) within a few ticks.

Tests

• test/rebase-lane.test.ts: I replaced the #6140 test "a busy builder's rebases go to idle builders". It pinned the behaviour this issue reverses, so the test was wrong for the new rule, not the code. The new tests cover the fork owner → author → assignee order and a busy author keeping the rebase.
• test/finishing-pages.test.ts: the approved conflicted pull's author, Mason, is busy while Torque is idle; the rebase is still queued for Mason. The old lending code would have given it to Torque, so this test fails without the fix.
• test/decide.test.ts: with Scout preferred but busy and Mason idle, Mason takes the issue; with both busy, Scout does.
• test/crew-ranked-pick.test.ts (new): the same case end to end through driveRepo, plus the idle count.

The type check is clean. The crew, decide, rebase-lane, finishing, tell and autonomy suites ran with 469 of 470 passing. The one failure is crew-sandbox-real.test.ts, which stops at load because this sandbox has no rg; the forge's check runs it. docs/FLOW.md now describes both rules.

To see it on the preview, watch the crew log. Rebase lines should name the pull's author as builder= and no longer carry for=. The picked lines should spread across builders as idle falls.

🤖 Generated with Claude Code

Approved pulls that conflict with their base are now brought up to date only by the builder who can push the branch. The builder picker also stops sending every issue to a busy favourite. I pushed nothing new after the triage note: it is about tagging the issue, not the code. Naming a pillar is for a person or the planner, and it doesn't change this pull.

Rebases of approved, conflicted pulls (src/crew/finishing.ts)

• ownBuilder picks the owner of the fork the branch lives in first, then the pull's author, then the agent assigned to it, then the least-busy builder.
• When that builder is busy, the rebase waits behind their current run.
• The #6140 lending to idle builders (lentBuilder) is deleted: a lent builder can't push to the author's fork, so every such run failed. The for field on the log line went with it.
• The count of failed rebases (two hand the pull to a person) is kept against the builder who actually ran them.

Picking a builder for new work (src/crew/route.ts)

• The new rankedBuilder treats the decider's per-builder probabilities as a ranking. The highest-ranked builder with nothing in flight takes the issue; when every builder is busy, the favourite does.
• An issue already assigned to a builder keeps that builder.
• p now reports the decider's probability for the builder who actually took the issue.

Tick line (src/crew/autonomy.ts)

• A new idle field counts builders with nothing in flight (idleBuilders), next to active and slots.
• driveRepo still starts one issue per 60 s tick. Starting several per tick would break the 71 tests that expect one pick per call. Since each tick now goes to an idle builder, active climbs to min(slots, startable, idle builders) within a few ticks.

Tests

• test/rebase-lane.test.ts: I replaced the #6140 test "a busy builder's rebases go to idle builders". It pinned the behaviour this issue reverses, so the test was wrong, not the code. The new tests cover the fork owner → author → assignee order and a busy author keeping the rebase.
• test/finishing-pages.test.ts: the pull's author Mason is busy and Torque is idle, and the rebase is still queued for Mason. The old code gave it to Torque.
• test/decide.test.ts: with Scout preferred and busy and Mason idle, Mason takes the issue; with both busy, Scout does.
• test/crew-ranked-pick.test.ts (new): the same case end to end through driveRepo, plus the idle count.

The type check is clean. The crew, decide, rebase-lane, finishing, tell and autonomy suites passed 469 of 470. The one failure is crew-sandbox-real.test.ts, which stops at load because this sandbox has no ripgrep (rg); the forge's check runs it.

docs/FLOW.md describes both rules. On the preview, rebase log lines should name the pull's author as builder= with no for=, and picked lines should spread across builders.

🤖 Generated with Claude Code