cron wrappers: unchecked mkdir -p LOG_DIR silently skips the pass (sibling sweep of #2196)

Goal

Sweep the sibling cron wrapper scripts for the same failure class #2196 fixed in scripts/cron_lesson_consolidate.sh: an unchecked mkdir -p "$LOG_DIR" (or an unprobed daily-log append) lets an uncreatable/unwritable log dir silently skip the wrapper's entire pass while the wrapper still exits 0.

Workflow gap

Surfaced by the #2196 code-reviewer (Claude, round 1, prose follow-up): ~10 sibling cron wrappers share the same unchecked mkdir -p "$LOG_DIR" silent-skip class — named examples scripts/cron_daily_healthcheck.sh:64 and scripts/cron_pod_audit.sh:57. The same brace-group-redirect mechanism #2196's task body documents applies wherever the wrapper redirects its pass into a daily log under an unchecked dir: the redirect fails, the group never runs, and the trailing exit 0 hides it.

Suggested direction (planner decides)

Apply the #2196 pattern per wrapper: a fatal()-style guard (stderr FATAL naming the path + best-effort push where the wrapper already has a push channel + exit non-zero) on the mkdir -p, plus an appendability probe where a brace-group redirect is the execution vehicle. Enumerate the full sibling set first (grep -l 'mkdir -p' scripts/cron_*.sh and inspect each wrapper's redirect shape); some wrappers may differ enough that only the mkdir guard applies. Keep each wrapper's routine-pass silence and exit semantics intact.

Acceptance criteria

• Every sibling cron wrapper whose pass is skipped by an uncreatable/unwritable log dir fails loud (stderr line naming the path + non-zero exit), or is explicitly recorded as not applicable with a reason.
• Existing wrapper tests stay green; routine passes stay silent.
• No changes to the wrapped consolidators/auditors themselves or crontab schedules.

Provenance

Surfaced-prose follow-up from the #2196 round-1 code review (workflow-fix-on-bug protocol, orchestrator-routed). Parent fix: #2196 commit 693a9b3d5440.