fix(cron): persist the junk-entry repair when no valid job remains; log types only

An all-invalid list filtered to [] skipped save_jobs (the 'if jobs and repair' guard), so every tick repeated the warning. Save whenever a repair ran (the shrink-merge still keeps concurrent valid jobs), and log the dropped entries' types instead of their raw values.

(cherry picked from commit 3b5b1aa61332cf79554fc2a24ae925908c37fe5d)

cron/jobs.py

@@ -1377,13 +1377,17 @@ def load_jobs() -> List[Dict[str, Any]]:
     if isinstance(jobs, list) and not all(isinstance(j, dict) for j in jobs):
         # Every reader and the due scan index records as dicts: one junk entry would crash the
         # whole tick and freeze every healthy sibling job, so skip it like the id-keyed map does.
+        # Types only: the raw values are arbitrary file content and must not reach the logs.
         junk = [j for j in jobs if not isinstance(j, dict)]
         logger.warning(
-            "Skipping %d non-object entr%s in jobs.json: %s",
-            len(junk), "y" if len(junk) == 1 else "ies", ", ".join(map(repr, junk[:5])))
+            "Skipping %d non-object entr%s in jobs.json (types: %s)",
+            len(junk), "y" if len(junk) == 1 else "ies",
+            ", ".join(sorted({type(j).__name__ for j in junk})))
         jobs = [j for j in jobs if isinstance(j, dict)]
         repair = repair or "non-object entries dropped"
-    if jobs and repair:
+    # Persist even an empty result, or an all-junk store repeats the repair on every tick; the
+    # save's shrink-merge still keeps any valid job a sibling wrote meanwhile.
+    if repair:
         save_jobs(jobs)
         logger.warning("Auto-repaired jobs.json (%s)", repair)
     _record_load_stamp(pre_read_stamp)

tests/cron/test_jobs.py

@@ -1735,6 +1735,20 @@ class TestJobsJsonIdKeyedMap:
         on_disk = json.loads(JOBS_FILE.read_text(encoding="utf-8"))
         assert [j["id"] for j in on_disk["jobs"]] == [job["id"]]
 
+    def test_all_junk_list_is_repaired_on_disk_without_logging_values(self, tmp_cron_dir, caplog):
+        """With no valid job left the repair must still persist (else every tick repeats it), and
+        the warning must not copy raw file content into the logs."""
+        import json
+        from cron.jobs import JOBS_FILE, ensure_dirs
+
+        ensure_dirs()
+        JOBS_FILE.write_text(json.dumps({"jobs": [None, "sk-leaked-value", 42]}), encoding="utf-8")
+
+        with caplog.at_level("WARNING", logger="cron.jobs"):
+            assert list_jobs(include_disabled=True) == []
+        assert json.loads(JOBS_FILE.read_text(encoding="utf-8"))["jobs"] == []
+        assert "sk-leaked-value" not in caplog.text
+