An agent run's log says where its time went: one timing line at the first push and one at the end #3665

For the owner's ask folded into #334 (building apps super fast): an agent run on a new app takes from 20 s to more than 10 minutes, and nothing says which part held it. Deploys already print a timing: line from src/apps/timing.ts; agent runs print none.

Done:

• [ ] src/crew/runner.ts takes a Stopwatch lap at the end of each step: clone, brief, harness to first push, harness to the end, wrap-up. It writes timing: first push Xs after the run started — clone … · brief … · … when the pull opens at the first push (src/crew/early.ts), and one more line when the run ends.
• [ ] The laps are written in the words the run log already uses. No new table, no new dependency.
• [ ] A test drives a run with the fake harness and a fake clock, and reads both lines with their laps in order. The test fails without the change.
• [ ] docs/CREW.md names the line in one sentence.

Files: src/crew/runner.ts, src/crew/early.ts, a test under test/, docs/CREW.md. Risk: runner.ts is large and busy. Keep the change to lap calls and two log lines. Fits: a server-side builder who knows the crew runner.

Parked by the crew: the check stayed red through 2 automatic tries (pull #3689 closed). Planner: split this smaller, or rewrite what done looks like; a person can also say what to try.

Parked by the crew: the preview's deploy failed and the decider saw no point in another try (pull #3776 closed).

Parked twice since a person last spoke here, so it is the planner's now. Every reason:

1. the check stayed red through 2 automatic tries (pull #3689 closed)
2. the preview's deploy failed and the decider saw no point in another try (pull #3776 closed)

The planner splits it, replaces it with a fresh issue, or defers it; a person can also say what to try. Nothing starts here until then, and the board lists it.

Split into #3778, #3779, #3780. Both attempts (pulls #3689 and #3776) made one change across src/apps/timing.ts, the runner, early.ts and the stand-in helper, and went red. The first attempt also overwrote test/crew-timing.test.ts (the /settings/crew test) along the way. The pieces now land one at a time: #3778 lets Stopwatch.line say 'after the run started', with no crew change. #3779 writes the end line from a finally on every path, as juniper asked, in a new test/crew-run-timing.test.ts. #3780 adds the first-push line.