#274 detect non-convergence when max-cycles exhausted

[VasilevNStas]

The judges CLI exits with code 0 even when --max-cycles is reached without achieving a fixpoint (convergence). The factbase keeps changing on every cycle, but judges reports "Update completed" with exit 0.

The problem

# judges always exits 0, even if max-cycles exhausted:
judges update --max-cycles=3 ...
echo $?  # → 0 (even if factbase never stabilised)

This means baza.rb treats the job as successful when in fact judges may not have finished processing all facts. The result is silently incomplete.

What this PR does

After judges update completes, entry.sh now scans stdout for the fixpoint message "has made no changes":

Condition	Before	After
Converged	exit 0	exit 0
Max-cycles exhausted, not converged	exit 0 🚫	exit 75 ✅
Judge error	exit ≠0	exit ≠0 (preserved)

Exit code 75 (EX_TEMPFAIL) tells baza.rb that the job failed in a potentially transient way — a retry with higher --max-cycles or fixed judge logic may succeed.

Why this works

The judges gem emits:

• "The update cycle #N has made no changes to the factbase, let's stop" → converged
• "Too many cycles already, as set by --max-cycles=N, breaking" → not converged

We grep for the presence of "has made no changes" in the output. If it's missing and exit code is 0, convergence was not reached.

Limitations

This is a workaround. The proper fix belongs in the judges gem — it should exit non-zero when --max-cycles is exhausted without convergence. A follow-up PR to yegor256/judges would be the correct long-term solution.

Checklist

• bundle exec rubocop — 0 offenses
• bundle exec rake — all tasks pass
• HoC ≤ 133

@yegor256 please review

[VasilevNStas]

@yegor256 — this PR is part of a 3-PR series that addresses a critical reliability gap in the baza.rb ↔ entry.sh pipeline.

The problem: When baza.rb pushes a job, entry.sh runs judges update with no time limit, no convergence detection, and no signal handling. If judges hang or fail to converge, the container runs forever and baza.rb's polling of finished? times out after 10 minutes with no diagnostic information — the user sees a silent failure.