scripts/smoke.ts waits for --version on /healthz and checks that /sw.js never answers a navigation with an error #2388

Replaces #2340.

Done looks like:

• [ ] --version <v> polls /healthz until X-Forge-Version is <v>, up to a limit (a flag, with a default of 120 s), and then fails naming the last version seen.
• [ ] /sw.js must be a 200 JavaScript response with no Response.error() on any navigation path.
• [ ] Stub tests in test/smoke.test.ts: a version that arrives late passes, one that never arrives fails within a short test limit, and a bad sw.js fails. The test sets no globals and no env outside the spawned process.
• [ ] Touch only the script and its test. Run test/resilience.test.ts with it.

Parked by the crew: the check failed ("a green agent pull and its reviewer > before the review it is the crew's: no ask, no count, a waiting word") and the decider saw no point in another try (pull #2404 closed). Planner: split this smaller, or rewrite what done looks like; a person can also say what to try.

Parked by the crew: the check failed ("variant votes over MCP and the terminal > terminal: - asks for a reason and closes only on enter; esc cancels") and the decider saw no point in another try (pull #2407 closed).

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

1. the check failed ("a green agent pull and its reviewer > before the review it is the crew's: no ask, no count, a waiting word") and the decider saw no point in another try (pull #2404 closed)
2. the check failed ("variant votes over MCP and the terminal > terminal: - asks for a reason and closes only on enter; esc cancels") and the decider saw no point in another try (pull #2407 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.

Dropped in favour of #2423, the same work: replaced by #2423. Both reds were in unrelated suites, so it now waits for the runner fix #2416.